star wars 1995-present 3 3/4 figs,, Unleashed (though I won't own two Vaders) vehicles, playskool, action fleet;
but I've quasi-broken out of being a completeist. I don't have every figure associated with Episode I or the vehicles or beasts. Just no attachment there and same loathing for all things Gungan as I have for Ewoks (actually worse).
Simpsons - Homers plus a few others. Have the THOH figs plus Burns, Burns Manor, Hank Scorpio, Smithers and now, apparently Scout Leader Ned diddly Flanders. No MOE
LOTR - started and abandoned. Only have FOTR Ring Wraith, Gandalf, Gimli, Legolas and Aragorn and they are all available except for Gandalf and Ring Wraith. Have TTT Ring Wraith and Horse, but will happily trade it away.
McFarlane Sportspicks - NHL mostly. Have all of NHL2-4 with the exception of a red Hull and a white Thornton. Waffling about only keeping the goalies though. These are the other acceptable things on display at work (Homer being the other).
Comics - from 1984-1994 or so, I collected comics and comic related cards. Mostly Marvel (X-men, spidey, DD, Thor, Hulk) and some DC (predominantly Batman titles, though some supe, catwoman), Image (Spawn, Gen 13) and some others. I fell out of it when big boobs became a super power that resulted in high comic book value
Only thing my wife collects is Disney movies/DVD's so I can relate Matt. Oh how I wish she would start with something. Much easier to rationalize a purchase that way, or so Koda tells me.