Just a thought Joe, consider a good quality large (250Gb say) internal HDD around £70 (Seagate/Maxtor) and bung it in a caddy (£25) which will work fine through USB2 or Firewire and is small and is gently portable and much cheaper - close to £200 for similar quality and size external drive.
In the future some time you can always bung it in the PC!