Simple, cheap USB brains for your DIY controller.
Just released, a $75 mainboard for the custom MIDI project you always wanted to build.
http://www.sparkfun.com/commerce/product_info.php?products_id=9108
32 channels of input, each can be either analog CC value or a binary NoteOn switch, output is through a USB connector to your machine. There’s even a community BBS for help and tips.
Not a no-brainer price, but it is a USB-based solution which differentiates it from the usual controllers like Doepfer and MIDIbox.