Arcade Warfare

The web sit certainly has a nice selection of online games, but if there is any one issue with it, it is that finding a game initially is rather obnoxious. All of the games are sorted by category (action, adventure, shooter, etc.), but each category can only be browsed, and so that impressive 5,000+ games now becomes a devastating hindrance.
Overall, Arcade Warfare has a fantastic selection of games that would appeal to a very wide range of individuals. Unfortunately, it's just too hard to find the good ones. Nonetheless, if the usability issues in question can be fixed, then this games portal could very well take off.