That's a bicycle-powered blimp built by Bill Watson in 1985:
It's the White Dwarf, built by Bill Watson and others for the comedian Gallagher in about 1984. This beautiful and innovative pedal-powered was used by Gallagher to do a Showtime special, Bryan Allen flew it 58 miles to set an FAI world record for that class airship, Bill and friends took it to Oshkosh, and then they put it behind Bill Watson's parents' house, where it stayed for about 14 years.
It still works! Link