[dnanian]

Nino:

It depends a lot on whether you want the copies bootable. If you only want ONE bootable one (or two -- whatever), you can make a partition for that, and then share the other partition by storing a series of sparse images, one for each full copy.

There's a FAQ entry that explains how; since the sparse images will grow to accommodate the data stored in them, you'll make efficient use of the storage, and don't have to worry about the exact size of the partition so much.

If you do want to partition -- which is the best thing, but not required -- you'd make the partition the size of the maximum amount of data you plan to grow the drive to. So, if it's a 60GB drive, but you think you'll never store more than 40GB on it, I'd make the partition 40GB+10% or so.

Make sense?