What is the cheapest way of running a mobile (cell) phone for two weeks in the whilst travelling in the US?

Getting a phone is USA can be difficult because you need an ID & long contracts, your best bet is RebelFone. They offer contract free US Cell Phone/Sim cards to travelers: a href="http://www.rebelfone.com/USA_simcards.asp" rel="nofollow"http://www.rebelfone.com/USA_simcards.as…/a