Space Race News reports that JP Aerospace has declared their intent to
compete for the $50 million America's Space Prize:

http://www.xprizenews.org/index.php?p=731

Their plans call for a three-stage approach to get to orbit, with an
airship taking people/cargo up to an inflated station at 140,000 feet,
with a separate orbital airship leaving from the station, propelled by
ion thrusters:

http://www.jpaerospace.com/atohandout.pdf
http://www.hobbyspace.com/AAdmin/arc...alAirship.html
http://www.jpaerospace.com/

JP Aerospace led to a couple of vivid discussions last year:
http://groups-beta.google.com/group/...k+to+Search&&d
http://groups-beta.google.com/group/... f3dbca01aa46