Best part is that they take money at three separate places:
a) First there's a listing fee - you have to pay money for your item to be listed, regardless whether it sells or not
b) Then there's the transaction fee, which you incur upon a successful sale of an item
c) An additional transaction fee if you want to get real money you made from your auctions
Not to mention that 3rd party companies you're transferring the money to may also take another cut...

