I find it interesting how music from the S.T.A.L.K.E.R series fits Fallout 3's wasteland so well. It's pretty calming to just go through DC in a Power Armor while listening to some nice music made for a game based on an entirely different area.
Just something I've noticed and found amusing while modding Fallout New Vegas. It's making me want to play S.T.A.L.K.E.R as well.