I did the same for a short while on friday - the wild swings were amazing. I made significantly less than you - 10% profit over a few hours as a protective stop kicked in a touch too early on one of my trades meaning i made 10 times less than i would have if that had not been closed.
Nail biting stuff though. Was getting in at 400 and out around 420 with a pretty aggressive leverage. Must say looking at the 200-300 range right now looks pretty juicy for the daily swing up to 300-400.
What kind of trades were you doing?