When I first got the game I'd play from around...ooh, maybe 8am til 3 or 4am the next day? So possibly up to 20 hours at a time, with a few bathroom breaks and trips to the kitchen to get some toast and tea in between. I don't know how I managed it - it was a very small and uncomfortable couch, and my laptop was really low quality. I've gotten a decent desktop computer since then, and out of curiosity tried playing the game on my laptop again. Nope, no way, the graphics were terrible and the game lagged something awful. I don't know if my laptop has gone downhill since then, or if I was just too engrossed in the game to notice the bad graphics back then.
I can't play for that long these days - I get bored with my games quickly, and have to go find something else to do. But I still open The Sims 3 and mess around for a few hours every day, and when I was away on holidays a few weeks ago I craved the game pretty bad xD. No wonder my family thinks I'm addicted.