I recently took up an older game to help me waste time of an evening. I'm playing Civilization 4 with the 'Rise of Mankind' mod installed, makes the game take a lot longer but there's massive changes to the vanilla game.
As soon as I get my new computer (should be any day now!), I'm going to go back to another older game and again play it with a mod rather than play the original version - STALKER: Shadow Of Chernobyl with the 'Secret Trails' mod.
I'm finding lately that aside from Forza Horizon, Skyrim and the soon to be released FarCry 3, there aren't that many new games that have much interest for me so I'm going back to older games.