CheeseTracker is an Impulse Tracker clone created by Reduz (aka Juan Linietsky). It is a so-called tracker. It is licensed under the GPL. It runs under GNU/Linux and Mac OS X.
Since version 0.8 it makes use of the Qt graphical toolkit. It has a JACK driver, thus its sound can be easily routed into other free audio software. It is possible to route the instruments through internal and external LADSPA effects.