Hulu has full NHL games on available for viewing online. If you haven’t heard of it, Hulu is a video service started by NBC and Universal. They have full movies and TV shows that you can watch for free with just a few commercials. The videos are good quality and look decent even in full screen.
At the moment they have game 5 of the finals available to watch but not game 6. I suspect game 6 will be up there soon. They also have lots of other NHL vidoes. Check it out: http://www.hulu.com/nhl