Our cat used to spend her time (most of the night, actually, to gauge from the noise) collecting erasers, pens, clothespegs, balls, hairbands, gidgets and gadgets and geegaws, oh, and her toys of course - batting them around the livingroom, chasing them down the stairs, and then finally herding them in under the (very low) chest of drawers in the downstairs hallway
OK.. I can't resist this one.
We had a cat that went to surgery for a stomach foreign body... she had over thirty pony-tail-holder thingy's balled up in her stomach! The owners flinged them across the room and they say the kitty "retrieved" them... yeah! They weren't really keeping track on that one!

I couldn't help but ask them if they asked themselves "where are the pony-tail-holders" when they kept having to go to the store and buy more!