I've wondered if there was a good reason to partition my OS/X startup disk. This is a good reason -- cloning the boot partition to a boot partiion of an external drive using Disk Utility:
After reading on MacInTouch of problems with Disk Utility's restore in 10.4.2 I was concerned about my weekly backup. I clone my startup disk weekly using Disk Utility's Restore, and this week was my first time using 10.4.2. The backup worked fine for me. I can start up from the newly cloned partition of my FireWire hard drive with no problem. I named the partition before cloning and the name was retained after the clone.