This is a feature that was present on OctaMED on the amiga (don`t know if ne of the other pc trackers have it). Basically the on/off command (mute) for each track is assigned to an individual number pad number i.e. 1 turns the mute on and off for track 1, 2 for track 2…etc.
May not be to everyones taste but of course would have to be configurable for the individual user, especially as sample choice is the default for these keys.
Also could anyone tell me if it would be possible to hook up a second keyboard (qwerty) with a pc + renoise and then assign short-cuts to this keyboard also? (new to pc controlled music making so unsure if this feature is even possible, wud be very 
if it is!)