Love the EP format for the weird collab aspect you sometimes get. You get split EPs, bit of variety, nice, loads of them.
Then splits where the bands cover each other. Random search gives the Boris/Asobi Seksu split:
Then you get EPs where artists collaborate directly and you get something new from it, like Macha Loved Bedhead (an all-time fave of mine):
Proper format, proper haircuts.