I run a very popular gaming site called Infinity Ward Nation (http://www.iwnation.com). Presently it's got a strong fanbase with anywehre between 50 and 100 users online at a time on the forums and twice that visiting the main site. In the month of April we had nearly 18 million hits and are keeping that pace steady.
IW Nation recieves approximately 4000 unique visits daily which is great for advertising space.
If you're interested in advertising please PM me your offers - include a copy of your banner/button as well.