I have collected / am still collecting so many weird things as well as "ordinary" stuff, the house resembles a junkyard. And whenever I move I take most of the stuff with me. Wife says I am a collectable myself

Nevertheless, here are a few examples:
* bottlecaps (more than a thousand, now all gone)
* postcards (still have about 400)
* baseball cards (still have more than 200)
* kinder surprise choco egg toy thingies (gone)
* 1:72 die casts of classic cars (still have 157)
* smallest currencies from various countries (last count I have 112 countries)
* old license plates of all my cars (still have somewhere in the attic)
* marbles (gone, though I still come across a couple here and there)
* F1 memorabilia (even car parts! some still there, including a stinky oil pan from a NASCAR Pontiac)
* beer bottles (gone)
* steins / mugs (still have about 60)
* banners from rock concerts / gala nights etc. (gone)
* Scorpions t-shirts (still have about 25 different ones, oldest dating back to 1979)
* expired phone cards (more than 600 still there)
* Xmas tree ornaments (gone)
* DVD movies /concerts (350+ of them)
* bonsai and cacti (as of now 17 kinds of bonsai, 23 kinds of cacti)
* first edition books (had over 150, donated them to a library back in 2005)
* european graphic novels such as Asterix, Lucky Luke, Tintin, Spirou, Cubitus, Johan et Pirlouit etc. (one full bookcase, lost count years ago)
* stamps (gone)
I guess it's enough... You get the idea...
In the beginning the Universe was created. This has made a lot of people very angry and been widely regarded as a bad move. - Douglas Adams (1952-2001)