External Tiny Utilities

This is a list of tiny utilities whose functionality is not provided by busybox. If you have additional suggestions, please send an e-mail to our dev mailing list.

Feature Utilities
SSH Dropbear has both an ssh server and an ssh client that together come in around 100k. It has no external dependencies (I.E. it does not depend on OpenSSL, using a built-in copy of LibTomCrypt instead). It's actively maintained, with a quiet but responsive mailing list.
SMTP ssmtp is an extremely simple Mail Transfer Agent.
ntp ntpclient is a tiny ntp client. BusyBox has rdate to set the date from a remote server, but if you want a daemon to repeatedly adjust the clock over time, try that.

In a gui environment, you'll probably want a web browser. Konqueror Embedded requires QT (or QT Embedded), but not KDE. The Dillo requires GTK+, but not Gnome. Or you can try the graphical version of links.

SCRIPTING LANGUAGES

Although busybox has built-in support for shell scripts, plenty of other small scripting languages are available on the net. A few examples:

microperl A small standalone perl interpreter that can be built from the perl source s via "make -f Makefile.micro". If you really feel the need for perl on an embe dded system, this is where to start.
Lua If you just want a small embedded scripting language to write new code in, this Brazilian import is lightweight, fairly popular, and has a complete book about it online.
rc The PLAN9 shell. Not compatible with conventional bourne shell syntax, but fairly lightweight and small.
forth A well known language for fast and small programs, decades old but still in use for everything from OpenBIOS to computer controlled engine timing.

For more information, you probably want to look at buildroot and TinyGentoo, which build and use tiny utilities for all sorts of things.