Apologies if this has already been covered. I'm about to switch (once the iBooks are finally updated) and I'm looking to buy an external Hard Drive (USB2 & Fireware connections) as I'll want to back up my data on a regular basis. I'll be wanting to back up information to the External HDD from my Mac and also my PC. My question is can the external HDD have multiple partitions with different filesystems or will I be able to just format it with one filesystem and still be able to back up info from my Mac and PC? And can anyone recommend a good make and model. Thanks.