HCI

Portable

http://www.wearablepersonalcomputer.com/

http://www.tekgear.com/twiddler3.html

https://www.kickstarter.com/projects/70308014/kings-assembly-a-computer-mouse-full-of-awesome/description

Split

Oobly - https://geekhack.org/index.php?topic=49721.0

Commercial

1. Belkin N52TE

1. Razer Tartarus

1. Logitech G13 Advanced Gameboard

1. ZeleSouris Mini Gaming Keypad

Single unit

https://github.com/technomancy/atreus