Swedish House Mafia is a group of 3 big name House DJs: Axwell, Steve Angello and Sebastian Ingrosso. I've seen them play in a lot of clubs and events in the LA area and they're fantastic at what they do. "One" is their most famous track as a group, recognized by many as the greatest house track of 2010. I must have heard this a million times over several events but it never gets old.
Some notable remixes include vocal versions featuring Pharrell, and another with Dragonette (a mashup by a DJ named Kaskade). Both can be found on youtube if you're interested :)