I actually collect cels because I think they are 
very cool, and I enjoy owning them ^^  I am a 
collector at heart, and always enjoyed looking at 
the Utena cels that were popping up on eBay a 
ways back.  I made a decision to start collecting 
cels from my favorite anime, went and read as 
much info about them as I could find, and then 
started buying.  I've learned my tastes go toward 
art/character of scene, and am still struggling 
to stick to that when affordable cels from cool 
scenes come up ^^;;