The A380 arrived in the U.S. today. The plane can carry 81,890 gallons of fuel and flies 8000 nautical miles, i.e., it burns approximately 10 gallons of fuel per nautical mile or 9 gallons per statute mile. The plane can seat 850 people if configured as an all-economy ship, so the mpg per person is approximately 95 (assuming the plane is fully loaded, which most planes seem to be these days). The Prius gets around 45 mpg in real-world driving and, though it can seat 5, is typically occupied by one person.
[I once saw an analysis of overall per-passenger-mile transportation cost, including capital investment and labor costs. The Boeing 747 was the cheapest form of transportation, period.]