Mount helper is a basic python script to help with mounting/unmounting usb mass storage devices. It can be a HUGE pain to mount/unmount usb devices from the terminal, especially if you don't have (or don't want to use) root.
Run the script. A menu will pop up and you can choose a device. If the device is mounted, it will be unmounted. If it's not mounted, it will be mounted. Easy.
This program requires that pmount be installed