Linux -- no hard drive?

I'm pretty sure you CAN do it because I thought I read where knoppix for example runs from a CD but I want to know --

which small linux distros can run from an sd card or usb flash drive?

my goal?

I have a dozen old P3 motherboards (733mhz) and I hate to junk them -- would like to build some MP3 players if possible.

would like something lean and fast that would boot up and auto start the player (and do a random play).

just have one folder of songs -- don't need to fast forward etc -- just PLAY.

so hopefully I can set it up and then disconnect the keyboard and monitor?

any help GREATLY appreciated. thanks.

Linux LiveCD option is what you're looking for... most of the Linux distros have it... just download it, burn it to a CD/DVD, then on the PC where you want to run it, change the BIOS to allow boot from CD... and away you go.
Most should also have an option to allow a boot from USB... same deal...

all this is dependant upon your mobo allowing boot from sources other than the HDD.

-tg

hate to be a brain picker but the sooner I get one built, the better -- any suggestions for a specific distro and media player as well?

will the program startup be a straightforward procedure?

some linux OS I've encountered can really be non-user friendly.

thanks so much.

ok thanks -- went with Lubuntu, love it.