I've got some good news and some bad news. The good news is there are new games available for Xbox Live's convenient Games On Demand service: runner up for fighting game of the year last year, Super Street Fighter IV and not often talked about SRPG Operation Darkness. You can now purchase these games, at least one of them being acclaimed, without setting a foot outside your home.
Ready for the bad news? Both games are priced at $40. This is bad news because I remember seeing Operation Darkness in the bargain bin many times for less than $20, and Super Street Fighter IV is much cheaper other places as well. Apparently, people will pay some pretty ridiculous prices convenience nowadays. If you don't mind getting out a little though, you can save a lot of money on these games.