Game playing has always been a huge hobby, if you can consider it a hobby. I love games of all kinds, but especially those with little or no luck involved. Like in chess, no dice=no luck involved.
Computer games, console games, board games, outdoor games (basketball, tennis, golf), and even indoor games like bowling, ping pong, and billiards.
That's my other hobby that consumes a lot of my time. Luckily, it's not nearly as expensive as reefkeeping.