550ex and the 10D - any tutorials or resources on using a big flash?

Anyone got any tips or links to how to use a flash like the 550ex? I want to learn the how to use a real flash like that, but am not sure where to start. I know some basics, but flash photography is a whole different beast.

Anyone know of any links or guides to what that flash can do and it's applications? I know it's a huge topic, so I am just looking for starting points on how to maximize the use of such a flash.

Thanks

http://photonotes.org/articles/eos-flash/

That was good information. Any other sites you know of now that talk about techniques, like bouncing techniques and tricks for using fills and such?