Qtpanel is a project mainly written in C++ and C, it's free.
a personalized fork of Mad Fish's qtpanel
This is a fork of qtpanel[1,2]. I changed some things in the source because it does not offer runtime configuration. This repo is probably not interesting for you.
[1] https://gitorious.org/qtpanel/qtpanel [2] https://bbs.archlinux.org/viewtopic.php?id=117528