I have:

-Nice track bike (NJS)
-Decent road bike (Fuji Team CF)
-Beater (1990 Specialized Sirrus SS)

I want:
-CX bike
-MTB
-Nicer road bike
-Touring bike for my (hopefully next summer) x-country tour
-Tri/TT bike

I'm good on track bikes, though. Unless I mess up my current track bike or it gets stolen, I don't see why I would need another.