Install to USB enclosure?

[kmoogle]

I'm considering purchasing a USB 2.0 IDE drive enclosure. My
motherboard supports booting from USB.

Can I install FC3 to the USB drive, e.g. as /dev/sda? I'd like to have
my full FC install on a portable drive, so that I can take it with me.
I have an existing OS on my main desktop that I don't have the liberty
of modifying at the moment and being able to run FC on demand would be
great.

Thank you.