LinuxBIOS doesn't support USB pen drives or USB compact flash. It does support ATA (IDE) flash devices.
On a normal (proprietary) BIOS:
Booting from USB is supported on many newer motherboards with a BIOS that supports this. I use Flonix to boot from a 64MB USB pen drive:
The Flonix forums are at:
http://www.flonix.com/support/viewforum.php?f=11
I also tried Puppy Linux (http.goosee.com/puppy/), but the USB bootloader (syslinux 2.08) didn't work for me. Using Knoppix 3.3 2-16-2004, I was able to install it's syslinux 2.04 bootloader:
# syslinux /dev/sda1
To make Flonix bootable, you can also use the above command from the Knoppix live CD.
(The first USB flash is /dev/sda, if there are _no_ SCSI drives. Otherwise, USB flash is the last "SCSI" device, i.e. /dev/sdc with two SCSI hard drives with special files /dev/sda and /dev/sdb.)
There are other Linux distributions built to be installed on a USB pen drive or flash.
Check out http://www.linux-usb.org/ for general Linux USB information.
BTW, I sent Flavio a private e-mail to flavio_groups@yahoo.com.br and it bounced. So, I'm forced to answer via the LinuxBIOS mailing list. Sorry.
Sincerely,
Ken Fuchs kfuchs@winternet.com