1300+ miles on a single tank of gas

Here's a guy who had his Toyota Prius converted to be a plug-in hybrid (PHEV), with a larger capacity battery pack and modified power management to increase its range on the electric motor. He got over 136 miles per gallon and went 2 months between fill-ups.

Then again, I've gone 1500 miles on my bike with zero fuel consumption.

(via davem5321).