Just how popular is South Dakota's "Twenty Bucks for the Road" program, in which residents of neighboring states are enticed to enter the Mount Rushmore State by the sweet, sweet siren song of free gas?

Answer: Very. The state is expanding the program from the originally planned 3,000 vouchers to 35,000.  35,000!

Never underestimate the People's love for free petrol. Or their willingess to drive hundreds of miles to get it.