Searching where to watch online Premier League and UEFA Champions League games I found several interesting posts/guides of how to make it possible to see these games online for free. You can check out this nice guide of using SopCast which is one of the most popular tools to stream TV online using p2p technology.
But unfortunately using SopCast isn’t enough to watch all leagues and all your favorite sports. That’s why I searched a little bit deeper and found this site where you can find all major leagues in many different sports together with link to service which provide possibility to watch current game online for free.
Including football you can search also for NHL, NBA, MLB, NFL/NCAA and other sports there and find best way how to watch them online without spending a cent!