Nico Nico Nii!~
Uh... not trying to brag, but I think I have 4000 cards. Not sure in the slightest, though. Haven't counted in quite a while.
The bulk of those are commons and uncommons from Platinum to Black & White.
My most valuable card (and because of the set it was printed in, most likely my rarest, too) is my Espeon* from POP Series 5, which is valued at $100. It and the Umbreon* from the same set are the only two Shining Star Pokemon to not have any holofoil anywhere on the card.