If you're in New York City with only $10 in your pocket, Julio Ortiz-Teissonniere has you covered.

Get an unlimited day pass MetroCard, he says. "It'll take you from the Bronx Zoo down to Coney Island and everywhere else in between for just $8.25. Just make sure you're done by 3 a.m. of the day after you bought it -- otherwise you'll spend a lot more than $10 on a yellow cab."

If you're in Italy, Diana Corridori could show you where to get a fantastic breakfast of cappuccinos, chocolate croissants and cookies for a ten-spot. And Jon Regas of Switzerland could help you dig up more than 40 singles on vinyl for that price. In Bhutan, Deki Dorji could feed you with fresh vegetables for a week.