Playing XBOX Gears of War is really fun, I am not really a good player, therefore completing wave 50 solo (playing alone) is tough for me, but from the game forums it seems that a lot of people claims their achievements easily, wonder if people care to spend a few minutes, complete wave 50 alone, take a picture, and share it?
I have created a Flickr group called "Gears Of War Solo Archievements Evidence", for people who really achieve that to upload a screenshot:
http://www.flickr.com/groups/gearsofwarsolo/
But to be honest, playing games like that is bad for health, playing lego is a healthier hobby I think, though much more expensive, the amount for buying an XBOX game is good enough for a small Lego set only.