Mounting USB Flash Drive
1. Plugin the USB Drive
2. Dmesg and see where the drive mounts.
3. Edit /etc/fstab /dev/sdd1 /mnt/usbkey auto users,rw 0 0
4. Make sure and create /mnt/usbkey
5. You should be able to mount and umount
6. If you have problems unmounting try theses command
lsof /dev/sdd1
fuser -muv /dev/sdd1
If you are finding that you can't unmount the device because device is busy
Run this command "kill -9 `lsof -t /dev/sdd1`" and then unmount.

I find this works very well with a KDE device on the Desktop because Konqueror seems to be keeping a connection with the USB Key.