I want to create a simple midi event processor. I want it to be small and compact. Really, all I need is a midi-in, a midi-out, and a CPU/firmware to do the processing. I found a commercial product that is fairly close to what I want: http://www.midisolutions.com/prodepp.htm , except the "programming" interface is too limited for my project, and the manufacturer won't provide the hardware information to create custom firmware. Are there any other commercial products I should look at, or will I have to DIY? I'm currently using a laptop, which works just fine, but I want to replace it with something simpler and smaller.