diff -uNr a/bitcoin/src/init.cpp b/bitcoin/src/init.cpp
--- a/bitcoin/src/init.cpp 971b82be435c99a1af9d5cacc9c05af7616f4af7ee1466efacd46d41eddc1c4d7da2fdb4a302aab7c99933d33ad2d613f3bfbe76fec67a71c6d4d1fe14ac142d
+++ b/bitcoin/src/init.cpp 2f6ab82ebab26369954cf9ca518e536a03c2a989d978823d6d78e1a924e601c855a8598863a5845727a93a457d49537ca91e027d69603abc1cb6f075e69af8d0
@@ -5,6 +5,7 @@
 #include "headers.h"
 #include "db.h"
 #include "bitcoinrpc.h"
+#include "shiva.h"
 #include "net.h"
 #include "init.h"
 #include "strlcpy.h"
@@ -177,6 +178,9 @@
 	    "  -verifyall       \t\t  " + _("Forbid the skipping of ECDSA signature verification between checkpoints.\n") +
 	    "  -setverstring    \t\t  " + _("Set a custom version string.\n") +
 	    "  -setvernum       \t\t  " + _("Set a custom version number.\n") +
+	    "  -shiva           \t\t  " + _("Enable the Shiva lisp listener (DANGEROUS!).\n") +
+	    "  -shivainit=<file>\t\t  " + _("Init file for Shiva (default: shiva.scm)\n") +
+            "  -shivaport=<port>\t\t  " + _("Listen for Shiva connections on <port> (default: 1336)\n") +
 	    "  -highs           \t\t  " + _("Set all transactions to have DER 'S' Value set to 'high'.\n") +
 	    "  -lows            \t\t  " + _("Set all transactions to have DER 'S' Value set to 'low'.\n") +
             "  -logtimestamps   \t  "   + _("Prepend debug output with timestamp\n") +
@@ -202,6 +206,13 @@
     fDaemon = GetBoolArg("-daemon");
     fCanEat = GetBoolArg("-caneat");
     fVerifyAll = GetBoolArg("-verifyall");
+    fShiva = GetBoolArg("-shiva");
+
+    if (!(mapArgs.count("-shivainit") && FileExists(mapArgs["-shivainit"].c_str()))) {
+      fprintf(stderr, "Error: If Shiva is enabled, MUST specify init file!\n");
+      return false;
+    }
+    
     fHighS = GetBoolArg("-highs");
     fLowS = GetBoolArg("-lows");
 
@@ -487,6 +498,10 @@
     if (fServer)
         CreateThread(ThreadRPCServer, NULL);
 
+    if (fShiva) {
+      CreateThread(ThreadShiva, NULL);
+    }
+    
     while (1)
         Sleep(5000);
 
diff -uNr a/bitcoin/src/knobs.h b/bitcoin/src/knobs.h
--- a/bitcoin/src/knobs.h 9b88b8f60d9a0ae98f9dd148dba06e132b6b1fc199719eacb3270fe6ce2af889422eee62c2cb08c3b93f22069aea880c657e771c4e4b4157a69c321550c8fc73
+++ b/bitcoin/src/knobs.h c6c24fca798bb308eb94d61854bd19a31384c9a6ee20ee9ff90e7e1cad6ee9fa93c44dfeb80265f61d4ca6cdf100bb530bb22ec4ab69a7cf0699acd19dc4a267
@@ -4,4 +4,6 @@
 #define  DEFAULT_CLIENT_NAME       "therealbitcoin.org"
 #define  DEFAULT_CLIENT_VERSION    99999 /* 50400 */
 
+#define  DEFAULT_SHIVA_PORT         1336
+
 #endif
diff -uNr a/bitcoin/src/makefile.unix b/bitcoin/src/makefile.unix
--- a/bitcoin/src/makefile.unix 09ac104678a444430d3ef0bdf6dbd07d875666493b2d938ac6aa7fb67abe840f2254f517055f4b5f90d0e86c83ee3dade77a58f1c37b7ab7b4c13598a5559adc
+++ b/bitcoin/src/makefile.unix bb1a279de6e10446b679b247dccd421efd70cee90177d797e08e078c49b9a03276d5b2e194f0459375b94b95877cbad34e8bb2a2d94246a13d5c5e71d8ee41c3
@@ -71,6 +71,7 @@
 DEBUGFLAGS=-g
 CXXFLAGS=-O2
 xCXXFLAGS=-pthread -Wno-invalid-offsetof -Wformat $(DEBUGFLAGS) $(DEFS) $(HARDENING) $(CXXFLAGS)
+CFLAGS=-lm -DUSE_ASCII_NAMES=0 -O2
 HEADERS = \
     base58.h \
     bignum.h \
@@ -87,6 +88,7 @@
     noui.h \
     protocol.h \
     bitcoinrpc.h \
+    shiva.h \
     script.h \
     serialize.h \
     strlcpy.h \
@@ -104,15 +106,18 @@
     obj/net.o \
     obj/protocol.o \
     obj/bitcoinrpc.o \
+    obj/shiva.o \
     obj/script.o \
     obj/util.o \
-    obj/wallet.o
+    obj/wallet.o \
+    obj-shiva/scheme.o
 
 
 all: bitcoind
 
 # auto-generated dependencies:
 -include obj/nogui/*.P
+-include obj-shiva/*.P
 -include obj-test/*.P
 
 obj/nogui/%.o: %.cpp
@@ -122,6 +127,13 @@
 	      -e '/^$$/ d' -e 's/$$/ :/' < $(@:%.o=%.d) >> $(@:%.o=%.P); \
 	  rm -f $(@:%.o=%.d)
 
+obj-shiva/%.o: shiva/%.c
+	$(CC) -c $(TESTDEFS) $(CFLAGS) -MMD -o $@ $<
+	@cp $(@:%.o=%.d) $(@:%.o=%.P); \
+	  sed -e 's/#.*//' -e 's/^[^:]*: *//' -e 's/ *\\$$//' \
+	      -e '/^$$/ d' -e 's/$$/ :/' < $(@:%.o=%.d) >> $(@:%.o=%.P); \
+	  rm -f $(@:%.o=%.d)
+
 bitcoind: $(OBJS:obj/%=obj/nogui/%)
 	$(CXX) $(xCXXFLAGS) -o $@ $^ $(LDFLAGS) $(LIBS)
 
@@ -139,6 +151,8 @@
 	-rm -f bitcoind test_bitcoin
 	-rm -f obj/*.o
 	-rm -f obj/nogui/*.o
+	-rm -f obj-shiva/*.o
+	-rm -f obj-shiva/*.P
 	-rm -f obj-test/*.o
 	-rm -f obj/*.P
 	-rm -f obj/nogui/*.P
diff -uNr a/bitcoin/src/net.cpp b/bitcoin/src/net.cpp
--- a/bitcoin/src/net.cpp 31eb2cbdf4f83f10ae8a7cdd3a69312ba6eafbecfafbeddf7546ce99847bd4f2a674037e2b89a0a7b91c37127d9770501c265a7977edb0ae0b3a5964272692f9
+++ b/bitcoin/src/net.cpp 1aae02f75e5ca6c54bf3eb97d2bca1ca675d64aa220653964dc44806898d3c3cbbb89ae6760637b2367054114af76dce5549e95d5a9a661b83f2f599bb68496f
@@ -1312,7 +1312,7 @@
     fShutdown = true;
     nTransactionsUpdated++;
     int64 nStart = GetTime();
-    while (vnThreadsRunning[0] > 0 || vnThreadsRunning[1] > 0 || vnThreadsRunning[2] > 0 || vnThreadsRunning[3] > 0 || vnThreadsRunning[4] > 0
+    while (vnThreadsRunning[0] > 0 || vnThreadsRunning[1] > 0 || vnThreadsRunning[2] > 0 || vnThreadsRunning[3] > 0 || vnThreadsRunning[4] > 0 || vnThreadsRunning[5] > 0
     )
     {
         if (GetTime() - nStart > 20)
@@ -1324,6 +1324,7 @@
     if (vnThreadsRunning[2] > 0) printf("ThreadMessageHandler still running\n");
     if (vnThreadsRunning[3] > 0) printf("ThreadBitcoinMiner still running\n");
     if (vnThreadsRunning[4] > 0) printf("ThreadRPCServer still running\n");
+    if (vnThreadsRunning[5] > 0) printf("ThreadShiva still running\n");
     while (vnThreadsRunning[2] > 0 || vnThreadsRunning[4] > 0)
         Sleep(20);
     Sleep(50);
diff -uNr a/bitcoin/src/shiva.cpp b/bitcoin/src/shiva.cpp
--- a/bitcoin/src/shiva.cpp false
+++ b/bitcoin/src/shiva.cpp bb607d1e17c0c4025e74d298c4fc3a65a824ed8c55401748fb6ff1f73fec5b5a2c92cf686516dcc119ffb28128bf07162cc70e7f144de2773a0c28832aab3c8a
@@ -0,0 +1,195 @@
+#include <string>
+#include <cstdio>
+
+#include <string.h> /* memset() */
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <netdb.h>
+#include <pthread.h>
+#include <fcntl.h>
+#include <getopt.h>
+
+#include <boost/algorithm/string.hpp>
+#include <boost/filesystem.hpp>
+#include <boost/filesystem/fstream.hpp>
+
+#include "knobs.h"
+#include "headers.h"
+#include "db.h"
+#include "net.h"
+#include "init.h"
+#include "util.h"
+#include "shiva.h"
+
+
+using namespace std;
+using namespace scm;
+
+static void *repl_runner(void *sock);
+static void init_shiva_hooks(scheme *sc);
+void ThreadShiva2(void *parg);
+
+
+//////////////////////////////////////////////////////////////////////////////
+/*                           Socketronic Housekeeping.                      */
+//////////////////////////////////////////////////////////////////////////////
+
+
+void ThreadShiva(void* parg) {
+  IMPLEMENT_RANDOMIZE_STACK(ThreadShiva(parg));
+  try {
+    vnThreadsRunning[5]++;
+    ThreadShiva2(parg);
+    vnThreadsRunning[5]--;
+  }
+  catch (std::exception& e) {
+    vnThreadsRunning[5]--;
+    PrintException(&e, "ThreadShiva()");
+  } catch (...) {
+    vnThreadsRunning[5]--;
+    PrintException(NULL, "ThreadShiva()");
+  }
+  printf("ThreadShiva exiting\n");
+}
+
+
+void ThreadShiva2(void* parg) {
+  printf("ThreadShiva started\n");
+
+  int port = GetArg("-shivaport", DEFAULT_SHIVA_PORT);
+  int listenfd, optval = 1;
+  struct sockaddr_in serveraddr;
+  pthread_t thread;
+
+  if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
+    throw runtime_error("Shiva: socket() fail.");
+
+  if (setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (const void *)&optval , sizeof(int)) < 0)
+    throw runtime_error("Shiva: setsockopt() fail.");
+
+  bzero((char *) &serveraddr, sizeof(serveraddr));
+  serveraddr.sin_family = AF_INET; 
+  serveraddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); /* ONLY localhost !*/
+  serveraddr.sin_port = htons((unsigned short)port);
+
+  if (bind(listenfd, (struct sockaddr*)&serveraddr, sizeof(serveraddr)) < 0)
+    throw runtime_error("Shiva: bind() fail.");
+
+  if (listen(listenfd, BACKLOG) < 0)
+    throw runtime_error("Shiva: listen() fail.");
+
+  printf("ThreadShiva listening on port %ld...\n", port);
+
+  while (!fShutdown) {
+    size_t size = sizeof(struct sockaddr_in);
+    struct sockaddr_in their_addr;
+    int newsock = accept(listenfd, (struct sockaddr*)&their_addr, ((socklen_t *)&size));
+    if (newsock == -1) {
+      throw runtime_error("Shiva: accept() fail.");
+    } else {
+      printf("Shiva: new session, connected from %s:%d\n",
+             inet_ntoa(their_addr.sin_addr), htons(their_addr.sin_port));
+
+      /*
+        This will probably have to change.
+        IMHO we do need multi-threaded Shiva, because having something like SLIME
+        working with it is The Right Thing, and this needs multiple REPLs.
+        On the other hand, it would also be quite fine to have exactly one REPL,
+        esp. if it persisted between sessions.
+       */
+      
+      if (pthread_create(&thread, NULL, repl_runner, &newsock) != 0) {
+        throw runtime_error("Shiva: thread spawn fail.");
+      }
+    }
+  }
+  
+  close(listenfd);
+}
+
+
+/* Load Shiva init file.  Mandatory. */
+static int read_init_file(const char *shiva_init_path, scheme* sc, FILE* fd_socket) {
+  FILE* fp;
+  fp = fopen(shiva_init_path, "r");
+  if (fp != NULL) {
+    if (fd_socket)
+      fprintf(fd_socket, "Shiva: using init file %s\n", shiva_init_path);
+    scheme_load_named_file(sc, fp, shiva_init_path);
+    if (sc->retcode!=0 && fd_socket) {
+      fprintf(fd_socket, "Errors encountered reading %s\n", shiva_init_path);
+      throw runtime_error("Shiva: failed to read init file!");
+    }
+    fclose(fp);
+    return sc->retcode;
+  } else {
+    return 0;
+  }
+}
+
+
+/* The room where it happens! */
+static void *repl_runner(void *sock) {
+  int sockfd = *((int*)sock);
+  FILE *fdin, *fdout;
+  scheme sc;
+
+  vnThreadsRunning[5]++;
+  
+  /* intialize the scheme object */
+  if (!scheme_init(&sc)) {
+    fprintf(stderr,"Could not initialize scheme interpreter!\n");
+    return NULL;
+  }
+
+  fdin = fdopen(sockfd, "r");
+  fdout = fdopen(sockfd, "w");
+
+  /* set standard input and output ports */
+  sc.interactive_repl = 1;
+  scheme_set_input_port_file(&sc, fdin);
+  scheme_set_output_port_file(&sc, fdout);
+
+  read_init_file(mapArgs["-shivainit"].c_str(), &sc, fdout);
+  init_shiva_hooks(&sc);
+  /* Jump into session */
+  scheme_load_named_file(&sc, fdin, 0);
+
+  printf("Shiva: closed session.\n");
+
+  fclose(fdin);
+  fclose(fdout);
+  close(sockfd);
+  scheme_deinit(&sc);
+
+  vnThreadsRunning[5]--;
+  
+  return NULL;
+}
+
+
+//////////////////////////////////////////////////////////////////////////////
+/*                            Now Taste The Meat.                           */
+//////////////////////////////////////////////////////////////////////////////
+
+
+/* Get current best blockheight. */
+static pointer btc_get_best_height(scheme *sc, pointer args) {
+  return sc->vptr->mk_integer(sc, nBestHeight);
+}
+
+
+/* Initite a shutdown. */
+static pointer btc_shutdown(scheme *sc, pointer args) {
+  CreateThread(Shutdown, NULL);
+  return sc->NIL;
+}
+
+
+/* Install the hooks. For each of the above, must do this: */
+static void init_shiva_hooks(scheme *sc) {
+  scheme_define(sc, sc->global_env, mk_symbol(sc, "btc-get-best-height" ), mk_foreign_func(sc, btc_get_best_height));
+  scheme_define(sc, sc->global_env, mk_symbol(sc, "btc-shutdown" ), mk_foreign_func(sc, btc_shutdown));
+}
diff -uNr a/bitcoin/src/shiva.h b/bitcoin/src/shiva.h
--- a/bitcoin/src/shiva.h false
+++ b/bitcoin/src/shiva.h 1276267c579b82ef2d3970f1a55eb55546250669f23b9c85da4b690ba779cc0820df34f5ec179804c59c936687ff209ec8ec360ca30d9d0344b6ac477574b0fc
@@ -0,0 +1,15 @@
+#ifndef SHIVA_H
+#define SHIVA_H
+
+#define BACKLOG    10  /* listen() */
+
+namespace scm {
+  /* We do this because the OP_* symbols in tinyscheme
+     clash with trb's script ops */
+  #include "shiva/scheme-private.h"
+}
+
+void ThreadShiva(void* parg);
+
+#endif
+
diff -uNr a/bitcoin/src/util.cpp b/bitcoin/src/util.cpp
--- a/bitcoin/src/util.cpp 66a8ac388136aceac7d24bd73c18b06445c2580849dd6c548d6684b5f1e9c19eafd3f71427476fd982383dcfd0425f34ce524eac1d8320fd990a28a1e4933288
+++ b/bitcoin/src/util.cpp 568ca27a4f90dc47f125880f64ee42dfeb0493a5e0ef79e314c3df1702920c21d7aea35cf197916a9881b569500c815d09e932f4668deef84507a26d7557b1cf
@@ -23,6 +23,7 @@
 bool fPrintToDebugger = false;
 bool fCanEat = false;
 bool fVerifyAll = false;
+bool fShiva = false;
 char pszSetDataDir[MAX_PATH] = "";
 bool fRequestShutdown = false;
 bool fShutdown = false;
@@ -787,7 +788,14 @@
 }
 
 
-
+bool FileExists(const char *path) {
+  FILE *file = fopen(path, "r");
+  if (file) {
+    fclose(file);
+    return true;
+  }
+  return false;
+}
 
 
 
diff -uNr a/bitcoin/src/util.h b/bitcoin/src/util.h
--- a/bitcoin/src/util.h f0c21c349b56516feac63c9cf8018c82b26583ad290a4b3610965e5a5a703d116671b1ef270395b8289c170b603630b5b7e493725e420e187ba1fbd326061ff5
+++ b/bitcoin/src/util.h b171f0824811472edb2e309537b772583a32b678550080f257d4b535bb62f46c04aaf0047d29500df6ca77a7e2c01d729b4536b7b7869061863012e39b6c026f
@@ -112,6 +112,7 @@
 extern bool fPrintToDebugger;
 extern bool fCanEat;
 extern bool fVerifyAll;
+extern bool fShiva;
 extern char pszSetDataDir[MAX_PATH];
 extern bool fRequestShutdown;
 extern bool fShutdown;
@@ -157,6 +158,7 @@
 std::string GetDefaultDataDir();
 std::string GetDataDir();
 void ShrinkDebugFile();
+bool FileExists(const char *path);
 int GetRandInt(int nMax);
 uint64 GetRand(uint64 nMax);
 int64 GetTime();