I just recently discovered that you can put a label on an ext2 or an ext3 filesystem, just like you can with a msdos/fat filesystem.
The reason I didn’t know was probably that it didn’t matter, but now with hal and gnome-volume-manager automounting removable disks, the disks in my usb enclosures are mounted as /media/usbdisk, that is, until I changed the label. Then it is mounted as /media/label, which is a lot more useful.
The label is set with:
e2label /dev/sdc1 yourlabel
Replace the partition with the one you want to set the label on.