Foreign coins: I've been collecting old coins since I was little. A local librarian gave me a large foriegn coin collection when I was 7.
Phantasy Star merchandise: I think this one is self exaplinatory.
Galoob Star Trek TNG action figures: I have everyone except the Benzite
Klingon weapons - So dar I have a Bat'leth and a MeqleH
Marvel Comics: At least 70 comics, most of which are Punisher and Spiderman.
Sega Genesis cartidges: I know this is a strange one, but I massed so many of the darn things when I was little that I decided to keep collecting them. The last time I counted them, I had 92.
Knives: I have a balisong (butterfly( knife, a kerambit knife, a large assortment of daggers, a handful of neck knives, two push daggers, one swiss "champ" knife, and two straight razors.
As far as obsessions go... I'm obsessed with Coheed and Cambria, Phantasy Star, knives, and Star Trek,