Translation: I think I managed to screw up several hard drives.
I have had a Maxtor external drive for quite some time (like 3 years or so?). Its main job was to hold our entire iTunes collection attached to the desktop (Gigantor) we have at home. Yes, note the use of "was". I should have listened more closely when Kate said iTunes wouldn't let her do certain things. Turns out those were symptoms of a drive that was going bad.
I ended up recovering some of it by purchasing Alsoft's DiskWarrior. Kate is paranoid (luckily) so she has backups on DVD in a safety deposit box. I also had a recent backup on another hard drive. Yep, another external one, for which I have a FireWire external enclosure that I just swap bare drives through.
It mounted, I was browsing files, and sure enough, that directory called "Music (Backup)" was there. Except, then, it wasn't. A system error about the disk being put away improperly. And the drive was/is toast, at least with the external enclosure I have, using the Oxford 911 chipset. There was of course the Panther Firewire Bug, but it seems there are some Tiger incompatibilities with some external enclosures as well.
Ouch. That'll teach me to try and do computer fixes early in the morning before I've had my first coffee. So, lessons learned -- if you notice any "funny" behaviour, immediately backup data (that was before the Maxtor went south). Secondly, if you notice *anything* funny with drives unmounting, unplug/power down the drive and do not touch them again or try and repeat the procedure. I may have actually nuked two drives in a row with this...I'm not sure yet until I get a different enclosure to test them with
This was a painful lesson. I have had "get proper backup solution" on my to do list for a while. What I really want is an external firewire hot-swappable hardware RAID solution, like the RAIDTech800 from WiebeTech (which I suspect is made by a company in Victoria called Synetic -- the box there is the Stardom 3600 -- $640CDN). This is not cheap, but it's pretty much bulletproof. A cheaper option might be something like the WiebeTech BayDock 800 - 2 or 4 drive enclosures, Mac OS X software RAID (review at Macs only). But, that doesn't solve backup -- with hot-swap, you can get three drives all with drive trays, and always keep one off site.