Helix folding bike
Ultimate folding bike
http://ridethisbike.com/folding_bikes.htm
http://www.montaguebikes.com/
Montague Paratrooper:
Folded Size 36" x 28" x 12"
http://www.flickriver.com/groups/paratrooper/pool/interesting/
Dahon Jetstream: 11.3" x 32.4" x 25.7"