I was thinking about this as this is a real indication that a game has you hooked. So far, surprisingly, the game I would buy again is FT. Would love a mint one but never seen one! FT was so addictive, fun with different modes and very difficult jackpots. A players pin but also for beginners as well.
I just sold my FT last night.
I will get another again someday.
From the past:
Centaur - I really loved the artwork, sounds and gameplay. Had one that I did a PF swap (PF was a second) Should not have let it go, they a hard to find
Shadow - the most balanced game, with reagrds to scoring, that I ever played. Many ways to score, not unlike FT. I like games like that...and hard too. I think I will end up with one again someday.