2. Mario Kart
I was skeptical of including Mario Kart on this list, as I am more than familiar with some of the cheating that existed on the DS version, but the last two iterations have more than atoned for it. Like most Nintendo games, the policing of the service makes sure you have fair games online. Mostly. Mario Kart 7 was the first game in the series to simplify online connectivity and the community couldn't have been happier. The customizable lobbies proved a huge success and promoted gamers to engage in friendly banter. It only gets ugly when you get blasted with a dreaded blue shell 5 seconds from victory. Overall though, Nintendo games are usually a place to make friends and have a great time. Mario Kart is easily one of the best communities online.