most newer games will work with modified resolutions, you typically have to set it manually in a config file though..
the only game i havne't been able to get to work is Knights of the old republic (I and II).. and Rome Total work looks awesome on the battlefield but poor on the campaign map..
try http://www.tigerdave.com/wgl/ for a short list of work arounds, although not all games that will work are on this list, you just have to try it.