Cars.
I currently own 3 (although I'm getting rid of my Conquest) and if I get a new daily driver, I'll sell the Prelude as well.
The budget to redo the mechanicals on my Trans Am was originally $8k. Now it's at $14k and climbing, because I keep adding things. Everyone I know thinks I'm retarded for putting that kind of $$ into a car that's worth maybe $3k with a stock motor / trans in it.
And, I'm going to look at new "daily driver" cars tomorrow. The one I'm looking at is ~12 years old, has 80k on it, and they're asking ~$18,600 - which looks like a good deal for what it is. All because I'd be miserable driving any new car in my price bracket.
And, both of the above cars will probably get 12-18 MPG and drink premium only.
That's my only real money pit.