http://www.ergodex.com/content.php?id=12
The DX1 Input System includes a Pad, a removable Tray, 25 numbered Keys with a storage tray, preprinted labels, an installation CD and a Quick Start Guide.
http://www.jazzmutant.com/
Lemur ))MultiTouch(( control Surface: LEMUR is a handy and modular touchpanel based controller designed for audio and multimedia real-time applications
http://www.iua.upf.es/mtg/reacTable/MusicTables/
This is overview on tangible musical interfaces is focussing on table-top controllers
http://ljcontroller.bzhtec.com/
Labjack U12 is very convenient to build custom controllers for software, without any soldering or to integrate into a hardware equipment (electronic circuit only without box, plugs, ...). It's small size (around 8x12 cm for version without the red cover) allows it to be embeded in small devices.