A scratch program named after Public Enemy's DJ, Terminator X.
terminatorX is protected by the GPL and features an easy to use GUI.
If both the sox and mp123 programs are present, it allows direct manipulation of MP3 files.
Once a sound sample is loaded in terminatorX's memory, you can play with it using your mouse though a laptop touchpad is much more convenient because of its feeling which is closer to the real thing.
terminatorX is freely available on the web at : http://www.terminatorX.cx
Latest version now features :

• multiple turntables,
• realtime effects (buit-in as well as LADSPA plugin effects),
• a sequencer