Conky is a system monitor for X originally based on torsmo. Since
its inception, Conky has changed significantly from its predecessor,
while maintaining simplicity and configurability.  Conky can display
just about anything, either on your root desktop or in its own
window.  Not only does Conky have many built-in objects, it can
also display just about any piece of information by using scripts
and other external programs.

Conky has more than 250 built in objects, including support for a
plethora of OS stats (uname, uptime, CPU usage, mem usage, disk
usage, "top" like process stats, and network monitoring, just to
name a few), built in IMAP and POP3 support, built in support for
many popular music players (MPD, XMMS2, BMPx, Audacious), and much
much more.  Conky can display this info either as text, or using
simple progress bars and graph widgets, with different fonts
and colours.