Ratbar: a nutritious breakfast snack for people on the move.

screenshot of ratbar

Ratbar is a menu, taskbar, and text output program for ratpoison.
The menu runs commands, the taskbar lets you see and pick windows in the current group, and the text output displays the output of a script run periodically.
GTK1 Ratbar documentation and code. GTK2 Ratbar (only refreshes on focus in or out)