MIDI File Mapper is a utility that allows you to remap the notes in MIDI files. This is particularly useful when converting GM drum patterns for a specific drum sampler or converting between loops for two different samplers.

MIDI File Mapper ships with some built-in mappings for popular drum samplers and allows you to create your own, as well as import maps from Cakewalk SONAR or Steinberg Cubase.

midifilemapper.codeplex.com
github.com/markheath/midifilemapper