I said no new features till after the 0.51 release. Well, I lied. This is a

vi editor for busybox, contributed by Sterling Huxley <sterling@europa.com>.
It adds 22k to the busybox binary when enabled.  Quite impressive!

Changelog

@@ -1,4 +1,6 @@
 0.51pre
+	* Sterling Huxley -- contributed a new vi applet!  This is a very
+	    functional vi implementation in Only 22k.
 	* Erik Andersen -- added env applet
 	* Erik Andersen -- Split utility.c into libbb
 	* Andreas Neuhaus <andy@fasta.fh-dortmund.de> -- fix for merging

Config.h

@@ -120,6 +120,7 @@
 //#define BB_UPDATE
 #define BB_UPTIME
 //#define BB_USLEEP
+//#define BB_VI
 //#define BB_WATCHDOG
 #define BB_WC
 //#define BB_WGET
@@ -334,6 +335,17 @@
 #define BB_FEATURE_TFTP_PUT
 #define BB_FEATURE_TFTP_GET
 //
+// features for vi
+#define BB_FEATURE_VI_COLON		// ":" colon commands, no "ex" mode
+#define BB_FEATURE_VI_YANKMARK		// Yank/Put commands and Mark cmds
+#define BB_FEATURE_VI_SEARCH		// search and replace cmds
+#define BB_FEATURE_VI_USE_SIGNALS	// catch signals
+#define BB_FEATURE_VI_DOT_CMD		// remember previous cmd and "." cmd
+#define BB_FEATURE_VI_READONLY		// vi -R and "view" mode
+#define BB_FEATURE_VI_SETOPTS		// set-able options,  ai ic showmatch
+#define BB_FEATURE_VI_SET		// :set
+#define BB_FEATURE_VI_WIN_RESIZE	// handle window resize
+//
 // End of Features List
 //
 //

applets.h

@@ -413,6 +413,9 @@
 #ifdef BB_UUENCODE
 	APPLET(uuencode, uuencode_main, _BB_DIR_USR_BIN)
 #endif
+#ifdef BB_VI
+	APPLET(vi, vi_main, _BB_DIR_BIN)
+#endif
 #ifdef BB_WATCHDOG
 	APPLET(watchdog, watchdog_main, _BB_DIR_SBIN)
 #endif

applets/usage.h

@@ -1689,6 +1689,13 @@
 	"$ uudecode busybox busybox > busybox.uu\n" \
 	"$\n"
 
+#define vi_trivial_usage \
+	"[OPTION] [FILE]..."
+#define vi_full_usage \
+	"edit FILE.\n\n" \
+	"Options:\n" \
+	"\t-R\tRead-only- do not write to the file." 
+
 #define watchdog_trivial_usage \
 	"DEV"
 #define watchdog_full_usage \

include/applets.h

@@ -413,6 +413,9 @@
 #ifdef BB_UUENCODE
 	APPLET(uuencode, uuencode_main, _BB_DIR_USR_BIN)
 #endif
+#ifdef BB_VI
+	APPLET(vi, vi_main, _BB_DIR_BIN)
+#endif
 #ifdef BB_WATCHDOG
 	APPLET(watchdog, watchdog_main, _BB_DIR_SBIN)
 #endif

include/usage.h

@@ -1689,6 +1689,13 @@
 	"$ uudecode busybox busybox > busybox.uu\n" \
 	"$\n"
 
+#define vi_trivial_usage \
+	"[OPTION] [FILE]..."
+#define vi_full_usage \
+	"edit FILE.\n\n" \
+	"Options:\n" \
+	"\t-R\tRead-only- do not write to the file." 
+
 #define watchdog_trivial_usage \
 	"DEV"
 #define watchdog_full_usage \

usage.h

@@ -1689,6 +1689,13 @@
 	"$ uudecode busybox busybox > busybox.uu\n" \
 	"$\n"
 
+#define vi_trivial_usage \
+	"[OPTION] [FILE]..."
+#define vi_full_usage \
+	"edit FILE.\n\n" \
+	"Options:\n" \
+	"\t-R\tRead-only- do not write to the file." 
+
 #define watchdog_trivial_usage \
 	"DEV"
 #define watchdog_full_usage \