eDrum MIDI Mapper » $10 (after 30 day trial period)
Provides trigger calibration and advanced MIDI re-mapping tools for edrummers looking to get the best performance out of sampled percussion instruments. 
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eDrum MIDI Mapper version 1.2 Released July 21st, 2008. Requires Microsoft Windows XP or Vista.
KSP Percussive » Free
A set of performance scripts for Native Instruments' Kontakt designed to enhance the realism of sampled percussion instruments. More info...
KSP Percussive version 1.1 released February 17th, 2006. Requires Kontakt 2 or higher.