hmmm... well there's the obvious given my lack of natural riding ability and how accident prone i am - getting a motorbike!!
I have skied and boarded in some pretty stupid places and have actually caused a mini avalanche
Kayaked on a river in flood known to be very very dangerous (in fact make that kayaked in some pretty stupid places full stop)
Abseiled forward down 100ft building.. on a mountain bike!!!
swam with sharks (only liccle ones though)
Cliff diving in windy conditions
stood in front of a moving car
:P