Just bought a Digimate image tank for image storage when on extended trips. I like to shoot raw images and find my 2 x 1G cards fill very rapidly (often in a couple of days). The device is slightly larger than a deck of cards and is fitted with a 40Gb Hdd of which 32Gb (largest Fat32 partition) can be used to transfer images from your memory card to the HDD at a single button press. The remaining 8Gb is useable for storage only from the PC. The unit has a backlit LCD display which shows the transfer and storage capacity status. These devices are available on ebay from both overseas and Australian dealers (I elected to buy from an Australian dealer). Power is supplied from an internal Lithium Ion barrery and lasts about 2.5 hours before recharging. The unit cost me $71 including registered post. It comes with a
genuine vinyl 
carry pouch, USB lead and 240V (multi voltage international) charger. A 40Gb Hdd cost a further $80. Now I can fill my 2x1G cards 16 times over on a trip away without worry. To retrieve the images from the Tank it is simply a matter of connecting via USB to the PC.