Save your money. Don't buy Apple's Time Capsule. You don't need it. It's a typical overpriced Apple peripheral that, while slick and easy, can be duplicated on the cheap. If you want to use Mac OS X Leopard's Time Machine over your wireless (or wired) network with multiple Macs to the same hard drive, read on.

When I first heard about Time Machine when Apple announced Leopard, the thought of backing up every Mac in the house to one central networked drive thrilled me. Finally, an easy backup solution for the whole family that would just work! So we bought the Leopard Family Pack as soon as we could and installed it with reckless abandon. Then, the snags started.

First, since Teresa and I both use laptops, we knew we didn't want to connect the backup drive to one of our Macs. Kimberly has an eMac--perfect. But Leopard requires a faster processor and won't run on her eMac. Ouch.

Shortly thereafter, we learned that Time Machine won't backup to a network-mounted drive. That was the greatest disappointment and made no sense to us, but suddenly, our hopes crumbled before our eyes. After a bit of Googling, I discovered Flux Capacitor. As it turns out, Time Machine can backup to a network drive, but Apple disabled that feature. Flux Capacitor re-enables that capability with a click, although for best results, we've learned the tricks to make this process as effective as possible, and I share them now with you.

1. If you haven't already, download Flux Capacitor and run it on every Mac you have running Leopard. Since it just flips a "software switch" in your system, you can delete it after you run it.
2. Connect your external backup drive to the desktop Mac that will host the drive via USB or FireWire. (It must be connected to a Mac running Leopard.)
3. Run Time Machine, choosing the external drive you connected. It will likely take a few hours to backup your entire drive.
4. Once Time Machine on the Desktop has begun its backup, use the other Leopard-running Macs to mount the Backup drive. To do so, choose the Desktop Mac in the Finder and double-click the backup drive.
5. On the same Macs, open Time Machine, choose the backup drive, and begin the backup.
6. Note: we found the initial backup via the network drives to be impractically slow, but we have a fairly slow (802.11b) network. If you find this initial backup to be too slow, remove the backup drive from the Desktop Mac, connect it directly to each networked Mac, and run Time Machine until a full backup has been completed. Once each machine has been backed up once, reconnect the backup drive to the Desktop Mac, return to step 3, and repeat the rest of the steps. Time Machine will thereafter only make the necessary incremental backups.
7. If you ever have a complete system crash and need to restore from your backup, connect the backup drive directly to the Mac in question, as we don't recommend trying to restore over the network.

Finally, figure out how much you saved, celebrate the option to expand your drive size in the future, and set that money aside for when your drive actually does crash, because with hard drives, it's a question of "when," not "if."

For non-Leopard Macs or for an online (off-site, which is safer), I recommend Mozy.com, which is compatible with both Mac & Windows with unlimited space. In fact, using the Desktop Mac, you can backup your entire Time Machine Backup hard drive with one account, thus backing up your entire home network for only $5/month. (They're not a sponsor, but we use them to backup our kids' Macs, since 2GB or under is free, and iTunes libraries excluded, they have less than 2GB of personal files.)