Does this exist?

Basically my Mac Pro isn't online yet, so if I want to install any new updates or software, or want to move stuff around I have to keep unplugging my external hard drive.

Is there such a USB/Firewire external hard drive that I can have plugged into both computers simultaneously and have both of them access?

Hopefully I'll have an airport extreme fitted into the mac soon....
 
Basically my Mac Pro isn't online yet, so if I want to install any new updates or software, or want to move stuff around I have to keep unplugging my external hard drive.

Is there such a USB/Firewire external hard drive that I can have plugged into both computers simultaneously and have both of them access?

Hopefully I'll have an airport extreme fitted into the mac soon....

Why don't you just buy a large capacity (1-2GB) usb flash drive?
 
you should check out the apple time capsule from what ive gathered its both an internet router and a wireless hard drive so you can have both computers connected to it.