Probably hundreds of hours on GTA, same for GTA Vice City and GTA San Andreas. Over 400 on FFXII, about 150 for Oblivion and Fallout 3. Just crossed the 100-hour mark for FFXIII. About 250 hours for MW2. Hundreds for both Rome: Total War and Medieval 2: Total War. I guess about a hundred hours for Half-Life 2, Homeworld, Age of Mythology and Warcraft 3. That's about what I can think of now.