Grizzly was made for KVR Developer Challenge together with Edward "Cyan" Blake (http://www.cyanwerks.com/). Grizzly ended up at 8th place and is a powerful drummachine featuring eight drumpads with built in filters and effects.
By using this plugin on single drum tracks like Snare or Kick you can replace the sound with any sample (.WAV file) you like. Great if you've tried everything to salvage a poorly recorded drum sound and got nowhere!
If you like this plugin but fancy something a bit more sophisticated, have a look at Drumagog. It's not free but it has a lot more features.
Controls:
WAV - The sample to play when the unit is triggered
Threshold - Signals above this level will trigger the unit
Retrigger - A time delay between triggers, to stop false triggering
Output - The overall volume of the sample playback