I just placed my preorder today for a family pack of Leopard. One thing I'm looking forward to is Time Machine. I have two macbook pros for me and my fiancee, a Mac Mini, and sometime soon an iMac I don't store sensitive data on the Mac Mini or iMac so backups aren't a big concern to me. My main concern is the two Macbook Pro's which we both depend on for work. I have a external firewire drive that I back up to approximately once a week and store in a fireproof save. I use SuperDuper so create a complete bootable mirror of them. I also have an Airport Extreme Base Station with a Western Digital 500GB hard drive. I store some items on that such as 70GB directory of clip art and also other important temp files and files that we use among the 4 computers. We have around 300GB free. We also use Chronosync which nightly backs up important directories such as Safari Bookmarks, accounting data, documents, mail data files, etc. Now with Time Machine I'm not sure how to change my plans. I plan to do the two backups which are stored in the safe but will Time Machine work with my Base Station Hard Drive? Both MacBook Pro's have around 100GB of data on them and I'm confused if it would need 100GB to back up or less or more. Am I better off getting a firewire drive that has to start on each MacBook Pro for it to work or will it work with a networked drive? If networked am I better off getting a 2nd dedicated base station drive or is a pure ethernet hard drive faster in speed?