If you want a fast route to custom synthetic percussion sounds, Inear Display thinks that you can plot it with its new Ephemere synth. Based on an FM synthesis engine, this also features a multimode filter and a couple of envelope generators.
There are actually 12 sound generation engines, each of which is assigned to a different note in an octave. Things get even more interesting when you consider that you can attach a randomisation setting to most of the synth parameters and a trigger probability per sound.
There are other randomisation options, too, giving the plugin something of a 'suck it and see' vibe.
Find out more on the Inear Display website, where demos can be downloaded for PC and Mac in VST/AU formats. Ephemere is currently available for the introductory price of $29 (the full price is $49).