Have a look at Go211.com if your feet get itchy when you're not riding a wave or jumping from a craggy mountain top.
Go211.com is touting itself as a community created by and for action sports athletes and enthusiasts (by that WebTwitcher's guessing they mean couch potatoes who like watching the extreme sports channels...).
In the style of all social networking sites you can create a personal profile and watch, upload and share videos of yourself and your friends doing your favourite action sports. You can rate your favourites and also play around with the music channel.
WebTwitcher is thinking of starting a profile by introducing her favourite extreme sport. Ironing. Perhaps a new channel that could be introduced when the site is launched out of Beta...