Everypony dreams of going to the Traders Exchanage in Rainbow Falls, where else can you unload all your old crud and turn it into something you truly wanted? It's like a flea market in heaven, and there's only one big rule: A trade is fair, so long as both ponies get something they wanted. A business-savvy pony like The Great and Powerful Trixie should have no problem making a profit here, unless a certain Exchange Overseer has some kind of vendetta against her this year...
(This is uncut, unedited speed-writing, in honor of the new episode 'Trade Ya', so there may be some minor spoilers for you if you haven't caught that one yet.)