There was thread ages ago about 'have you tried any unusual sailing postions' a while back but I can't find it. Anyway have you ever tried to do it standing up? It is quite good fun if it's not too windy. I just thought of it today bored in light air and tried it. A bit like a big surf board. Once the wind picks up it gets more difficult. I found it easiest if you put one foot behind the footwell and one beside it. You can lean out a bit by hanging on the sheet but you can't lean out enough to get the same angular moment that you can when hiking normally but I think some sort of rudimentary grab line could be rigged up to help with that.