I got Universe at War: Earth Assault for $5. It comes with a one-month subscription to Xbox Live, which goes for about $4 on average. (You can get a month for $3.50 if you buy 13. A single-month card actually costs $7 retail.) Net, the game cost me about one dollar. Basically, I have to watch the introductory movie to get my money's worth. I paid more than a dollar for a floppy disk containing a demo of a DOS pinball game at a flea market in the early 90s.
Hopefully it will be a little better than that. I don't know when I'll get around to it since I'm working on Hellgate: London and Company of Heroes right now, but Company of Heroes hasn't really thrilled me, so maybe my desire for RTS will resurface sooner than expected. I think I'm slowly developing my skills at not playing games that aren't thrilling me, and moving on to something else. Company of Heroes isn't bad, and in fact there's a lot to like about the innovative things it does with the genre, but it's just drab and slow most of the time, in an extremely uninteresting WWII setting. But, I think I'm close to the end, so I'd like to finish it out before I move onward.