If you were home schooled through Kindergarten, or grew up as a single child, the concept of sharing may be foreign and difficult to understand, but allow us to break it down for you: By giving someone something they want, there's a good chance you'll receive something you want in return, either immediately or down the road!
It's a system that's worked well for millennia, and now it comes to Uber Entertainment's Super Monday Night Combat in the form of Steam Trading support, which allows Steam users to trade in-game items. To celebrate, two Super MNC hats ("Gunslinger Hat" and "Assassin Helmet") are now available in Team Fortress 2, earned by achieving levels five and 20 (respectively) in Super MNC. Conversely, TF2 costumes have been added to Super MNC: An Engineer's uniform for CombatGirl and a Soldier uniform (plus rocket launcher skin!) for Megabeth, unlocked at levels 10 and 15.