Catch 'em all. Check
As posted on Joystiq, this girl (well, she's 21) recently got into the Guinness Book of World Records for having the largest Pokemon collection at over 12000 items. In fact, she says that since it was counted, the number is now up to 13,400 items sprawled through her mom's house. It took her 13 years to amass this collection (so a little more than 1,000 Pokemon things per year).
I think if I had a collection and had the 10 or so Snorlaxes that she has in the upper right hand corner, I would say 'ok, that's enough Snorlaxes and Mudkips now. Think the next thing I will put money toward will be an apartment of my own' "
Telegraph.co.uk also has a small article on Lisa Courtney's Pokemon Center Europe and how it takes over the entirety of her mom's house.