I replied to your other post here but will echo on this thread. The WikipediA article seems pretty complete on this subject.

Dan is an official (Honda) Hydrogen Economy Convert!
Houston Hybrid and Hypermilers Club <106mpg.com>

Best commute = 14.3mi @ 114 MPG (sg2)
Best (non-trivial) tank = 769mi @ 85.7 MPG (fcd)
MPG Centurion-Hybridfest 2007-Prius II-26mi @ 106 MPG (sg2)
Dan <11011011> @ CleanMPG.com