I have a 2005 Toyota Prius, four months old, and have just started seeing this exact same behavior the last two times that I have gone to the gas station. Mind you, after noticing this, I only fill the gas tank to what I assume is maybe three-fourths the way so it doesn't erupt gasoline from the nozzle.

Still kinda weird. Called a Toyota service rep in the evening, and he had heard of this happening, but had no idea what was causing it. He recommended calling back during normal work hours to catch up with one of the more knowledgable people in-house to see what they thought. I guess I'll be doing that and seeing what happens.

Otherwise, the spaceship is so much fun.