I did once manage to right Atum without actually getting onto the board, from the water I grabbed the end of the board and using my superior man strength* I just pulled down and brought the boat up. Not sure whether this is possible using the tree trunk on the Badger. Maybe I'll try it some time!
On the Badger we have the take ups for the kicker and cunni lead out and down the racks, these can be pulled if required, or as others have said the spinni sheets either side of the block also work.
My technique for getting back in the boat is to get Alex to go to leeward, I grab the trap and put my feet onto the rack, then just stand up and climb in. I have to be quick with this, as Alex weighs roughly the same amount as one of my legs, so even with him wiring out the other side I can capsize the boat back on top of me!
*Whether it was my superior strength or just being a bit of a pie which enabled this feat, I wouldn't like to say either way!