If you use a recording host that supports VSTi, you need to check out Jamstix --
http://www.rayzoon.com/ It's a virtual drummer for rock, blues, and funk.
This thing has a "free jam" mode that will look at MIDI data or audio (read: your bass) in real time and play differently based on how loud you play. You play softly, Jamstix switches to side stick. The patterns it plays are generated on the fly or you can choose from a huge sequence library. I could go on and on about the features; it's really packed.
Right now it's on sale for US$79. This program is worth every penny and the support is outstanding. Get the demo and play with it in your host.
NOTE: I don't work for Rayzoon (I wish I did). I'm only a very happy customer.
