Xbox Connect is a program that tricks the Xbox into thinking it is hooked up like a LAN, also known as system link. By downloading this program onto your PC and a router connected to both your PC and your Xbox you can play system linked game with people all over the world. Xbox Connect is completely free and is one of the alternatives to Xbox Live. There is another called Xlink Kai that does the same thing as XBConnect with other features.
Along with the above function XBConnect allows users to find other gamers looking for a match. Due to the large amount of lag that users may experience if in a game where the host is far away it's suggested that you should only join games that are located close within your same state, province, or territory.