From the IXDA List...
Wiring
http://wiring.org.co
Phidgets
http://www.phidgets.com
Calder toolkit
http://www.cs.cmu.edu/~nx6/pubs/Lee_HWTK_DIS_04.pdf
Context Toolkit
http://www.cs.berkeley.edu/~dey/context.html
DART
http://www.gvu.gatech.edu/dart/index.htm
iStuff
http://media.informatik.rwth-aachen.de/istuff/index.php
Papier-Mâché
http://guir.berkeley.edu/projects/papier-mache
Sketchtools
http://www.sketchtools.com/
