Expatistan
Expatistan.com was founded in 2009 by Gerardo Robledillo, a software engineer specializing in web applications. An expat himself, he created Expatistan to solve a problem that every expat faces; How much money will I need in my new city? Expatistan runs one of the biggest collaborative cost-of-living databases of prices in the world. This database is constantly updated and improved in a collaborative way by expats all over the world.