Dont know if you guys have seen this or not.
Its called Parkour, freerunning/climbing, kinda like skateboarding without skateboards. A growing freesport.
I cant help but to think how it could be applied to tree climbing (with gear of course)
This is a quick taste:
http://www.youtube.com/watch?v=jquXc...elated&search=
This shows some techniques:
http://www.youtube.com/watch?v=J1o8WJ69rdc&NR=1
This is a bit longer clip:
http://www.youtube.com/watch?v=uUksaD-JJgI