Hey there -
so you guys are browsing the cafe (seen other places calling their off-topic areas as "the pit" or other rather agressive names, so let me try the apropriate way to put this...) .
OK, Cafe-Style:

Excuse me, but have you heard about wikiloops?
No? Well, its just been set online on april 1st 2011, and theese fellows keep on posting their little homerecordings for other people to jam along or do a remix.
Its a free thing, so if you are interested in practising to backings or do some homerecording and would like to participate, you should give this a try!

Yes, I am involved in this, as 95% of the tracks containing basslines were posted by myself, adding some saxophone tracks...

Heres the link leading to a short explanatory clip on the project to give you a good start:

Last wish: If you think this is something worth checking out, please give some feedback here so other users will notice and be assured this is not spam for a rip-off thing, so any feedback is appreciated!