Additional hardware

Hi this is my first post. I'm planning on buying a beagle board for a
couple of reasons. One is so I can screw around with linux and other
operating systems other than windows. I used linux in college but I've
never really owned a linux machine. The other reason is because I've
been working on an artificial intelligence program and I would like a
way to be able to take stereo videos for use in the program. So I'm
planning on using the beagle board and 2 webcams to make my own stereo
video camera so I have something a little more handy to take video
with than a laptop or pc .

So here's my questions:

1) Are there any good power supply and rechargeable battery
combinations someone can recommend so I'm not tethered to an outlet
all the time? It doesn't have to be a huge battery just enough to take
a few minutes of video.

2) Do all sdhc cards or thumb drives work in the beagle board? Also I
would like to put the entire operating system and programs in the sdhc
cards or thumb drives so if I fool around with multiple operating
systems and projects I don't have to install and uninstall stuff all
the time. Is it possible to do this or does part of the operating
system have to be in the beagle boards own flash memmory?

3) Is there any other hardware I might need to buy besides what I've
mentioned already?

4) Also what are the advantages of the the different linux distros
that work on the beagle board and what would you guys recommmend for
what I'm doing?

Thank you for your help.

Mike

(1) If you look around for info on the "Iron Man Suit" costume made
with Beagleboard and Arduino, you'll find some diagrams of his
portable power supply and portable USB hub setup. Look in the forums
on http://www.arduino.cc/ or http://www.instructables.com/id/Iron_Man_Suit_with_Tech/
-- Enrique has been on this list too

(4) I'd like to hear if there are alternatives, I'm planning to use my
BB with OpenCV under Angstrom, a fellow I know here in the silicon
valley is also using OpenCV with Angstrom for a robotics project.

cheers,
kb