Enter the Mad Hatter, aka Kat, and her large collection of hats. From seasonal hats, to wolf hats and dragon hats, to epic hats, she's simply teeming with hats. It has not only taken over her bank, but her alts as well. At least I try to keep my collections to one character. Sort of. Okay, not really.
Luckily, hats on gnomes are not as ridiculous as hats on tauren. I used to be quite entertained by my friend and guildie's hats, as she was a female tauren. We had a running joke regarding the alligators in Dustwallow Marsh, as they kept giving her the most ridiculous hats. One evening I laughed so hard I had a mild asthmatic attack. I wish I had taken screenshots.
As for collections, pretty well any item acquired during a seasonal event, I still have stashed in my bank. I also have quite a number of non-combat pets, and have gone out of my way for a few of them.
Do you have any collections? Are there any items that really give you a laugh? Do you find yourself grinding just for silly items that you must have?