I got my DMC Xclef 500 yesterday and, after a little bit of Googling, figured out how to set it up. Since no one appears to have anything on the net relating specifically to setting this up (I inferred from other documents), I thought I'd just mention the few easy steps I took on my Debian Linux box.

The options I needed in my kernel were to enable SCSI devices in general and SCSI hard drives in particular, USB mass-storage devices, and the DOS FAT filesystem. Once I had those ready to go, I simply mount -t vfat /dev/sda1 /media/xclef, though obviously your mount point will differ. I'm sure I could futz for a while and figure out how to mount it so that I don't have to be root to copy files onto the player, but I don't really care that much.

One note about potential buyers: it's really huge. If you're expected an iPod or something, don't get this player. I love it already, without even having heard it yet, but it's large and not particularly light, mostly, I'd guess, because of the brilliant idea to make the thing with a standard laptop hard drive, thus making the swapping out of drives an easy, do-it-yourself proposition in case you want more space or a drive fries or something.