It worked out of the box fore me, only needed to set it up in /etc/fstab.
It is preformatted to fat32. The only issue is that the real size of it is not 250 but 233gb and the cable is only 20cm (http://www.allconversions.com to see this length in other units).
But all over fine, gets kind of hot, but surprise surprise :)

See more specs at: http://www.lacie.com/products/product.htm?pid=10468

Hi. I just bought this Hard Disk and connected it to my computer which is running a Gentoo Linux

Kernel name: Linux 2.6.17-gentoo-r8 #1 SMP Tue Sep 26 20:57:02 CDT 2006 i686 Intel(R) Pentium(R) 4 CPU 3.00GHz GenuineIntel GNU/Linux

This Hard disk comes with a preformatted partition in FAT32, so, my fstab configuration for that device is:
/dev/sda1 /mnt/usb vfat noauto,defaults,user,umask=0 0 0