USB 2.5-inch IDE/SATA Bridge Adapter
Brando has made available the USB 2.5-inch IDE/SATA Bridge Adapter which is pretty much self-explanatory - it forms a bridge between a USB port and one IDE, SATA or CompactFlash memory card slot. This means and standard SATA or IDE hard drive will be able to function as an imprompty external drive whenever you need it to, just make sure that it is properly formatted beforehand. It will retail for $22 and works with both Mac and Windows platforms.