Feeling noble, I shlepped downstairs this afternoon to the fitness center in our apartment building, determined to burn off a few hundred calories on the treadmill. I got myself organized, and just before turning on the machine, I turned on one other indispensable machine: my iPod.

But instead of the usual display of playlists, albums, and artists, I got a completely unexpected display that said, in four languages, “Use iTunes to restore.” (”Utilisez iTunes pour effectuer une restauration” sounded friendlier, while “Zum Wiederherstellen iTunes verwenden” sounded downright hostile, and the Japanese ideographs were simply inscrutable).

Say whaaaat? I didn’t want to restore anything; I was perfectly happy with the playlists and the songs just the way they were. But more importantly, I realized that I simply could not spend an hour trudging away on the treadmill with nothing to listen to. Sometimes I exercise at a gym a few blocks down the street, where they have a bank of 8 televisions on the wall, half of which have a more-or-less real-time form of text captioning, so you can figure out who’s saying what to whom — on CNN or Who Wants To Be A Millionaire or the afternoon soap opera or the Sunday afternoon football game — even if you don’t have your headphones with you. That’s been a lifesaver on the few occasions when I’ve arrived at the gym and discovered that I left the iPod at home … but the gym in my building has only one television, and it was broken today.

So I went back upstairs to my apartment to “restore” my iPod, whatever that was intended to mean. I assumed that the problem was simply that the onboard software had gotten corrupted, and had to be reinstalled. But alas, it was not to be: both my desktop and laptop computers complained about a mysterious “error” that occurred when they attempted to reinstall the iTunes software. Various utility programs were equally unable to erase, or even access the 4GB hard disk inside my little nano device. I had listened to a song on the iPod as recently as midnight last night — but somehow, in the middle of the night, the hard disk had died. Poof. Gone. Muerto.

I’ve owned this iPod long past the warranty period, so for all practical purposes, it was permanently dead. Oh, I suppose I could have made arrangements to send it back to Apple for repair — and it’s now sitting in a desk drawer waiting for me to feel sufficiently inspired to do just that. But it will be a hassle, and it will take a long time, and I’m convinced that it will cost almost as much (if not more) to get it repaired than it would to simply buy a new one.

And what would I do while I was waiting for the repaired device to be sent back to me from Apple’s Galactic Headquarters? A moment of panic: I wouldn’t be able to exercise, ever, until it reappeared. I’m serious — my whole exercise ritual is centered on a specific playlist of songs (actually, five different playlists, depending on whether I intend to exercise for 30, 40, 50, 60, or 90 minutes), and I simply can’t imagine spending an hour in the gym in total silence. It’s sick, I know it’s sick, and I keep telling myself that for roughly 25 years before the iPod appeared, I was perfectly happy jogging, running, or shlepping on the treadmill without any earplugs in my ears, and without music booming into my head. I didn’t even need a Sony Walkman, but now I can’t function without an iPod.

So it took only a moment’s thought before I put my jacket on, and trudged down Broadway to the nearest Radio Shack. In the interval since I bought my defunct 4GB nano, a new 8GB machine has arrived on the scene — a welcome relief, since I had reached the point where every downloading of a new song required deletion of some other song. It was an interesting Darwinian process that forced the less-popular songs in my repertoire to be slowly discarded, but it was nevertheless frustrating.

When I returned home with my new nano, I encountered another problem. It seemed like a good time to copy my entire iTunes library of roughly 1,000 songs from my desktop computer to my laptop, so I could use the laptop to synchronize my music from now on, whether I was at home or on the road. No problem copying everything from one computer to another, but when I attempted to download everything from the laptop to the new iPod, I got a polite, but firm, error message indicating that I could not download the 128 songs that I’ve purchased from the iTunes music store over a period of months or years, because they had already been downloaded onto the maximum number of allowable computers.

When I got my first iPod (in 2001, I think) and when the iTunes music service was first established, I thought it was exceedingly generous of Apple to authorize its purchased music to be copied onto five different computers. Who would ever need anything more than that? After all, I had only one desktop computer, one laptop computer, and one iPod … and I didn’t anticipate that I’d ever need much more than that.

Well, laptop computers do break down from time to time, and I finally decided that I was so dependent on a laptop when I was traveling on business that I should have a backup laptop in addition to my regular one; among other things, it gave me an excuse to upgrade machines every year or two, and it usually meant that my backup machine was older, slower, with less memory and a smaller display screen. But in terms of the iPod situation, that was okay: I was still dealing with a total of three computers and one iPod device.

What I forgot, though, was the ” technology trickle-down” policy that has existed in my family for years. When I outgrow one of my computers (or need a convenient excuse to get a new one, even if I don’t really need it), I tend to hand off the older computer to one of my kids … or my wife … or my siblings … or my retired father or mother … and, on rare occasions, even a desperate friend whose 7 year old machine has finally crumbled into dust. And along the way, the same thing has happened with iPods: I’ve probably had five or six different iPods over the past five years, as Apple has continued producing newer, smaller, sexier machines with more and more and more storage capacity. I don’t have an iPod Shuffle or an iPod Video device yet, but I’m now on my third nano.

Meanwhile, in addition to the desktop and two laptops that I use, my wife also has a desktop and two laptops, both of which are “hand-me-downs” that I once used. And she, too, is on her fourth or fifth iPod, with earlier models being donated to appreciative relatives, friends, and colleagues.

All of these machines have had iTunes installed, and all of them have been attached, at one time or another, to multiple iPods. So instead of the original, simple formula of one iTunes-purchased song being installed on five computers, which was attached to just one iPod, we now have a hodge-podge of N computers and N iPods, all of which have been interconnected in various combinations and permutations over the years. If I had anticipated that the interconnections would mushroom so quickly, perhaps I would have been methodical enough to keep a careful written record of everything … but I didn’t.

However, I did remember one previous occasion, a couple years ago, when I exceeded the maximum number of computers that iTunes would allow its purchased music to be stored on. It was when I handed off an older laptop to my father, acquired a shiny new Powerbook, and attempted to reinstall my music in much the same way that I attempted today. Having gotten the same stubborn error message at the time, I discovered that one simple solution was to “deauthorize” the older laptop, since my father had no interest in iPods or iTunes; and I also discovered that (for reasons I never did understand) Apple would allow a computer to be deauthorized only once per calendar year. My father still doesn’t listen to iPods or iTunes, and his older laptop is still deauthorized, so I guess Apple’s policy isn’t so unreasonable.

In any case, I thought that my current dilemma could be solved by deauthorizing the iTunes account on my desktop computer, and simply doing all future iTunes-related activity on my laptop. Good theory, except that the deauthorization command asked for an “audible account number” and password. Audible account number? Whazzat?!? Is that the iTunes account number that I use for purchasing and downloading songs? Nope. The account number for the .Mac service that Apple provides? Nope. The user-id for Mac OS X on the computer? Nope. Well, maybe it was one of those account numbers, but it didn’t like the various passwords I supplied with those familiar account numbers. After wasting another 15 minutes without any progress, I gave up.

But there was one more thing to try: although iTunes had explicitly told me that it wouldn’t download the “unauthorized” copies of my purchased music from my laptop onto my iPod, I had not actually attempted to play the songs on the laptop. When I did so, I got another error message — this one telling me, once again, that I had exceeded the maximum number of copies allowed, but also politely asking me if I would be willing to pay $0.99 to “reauthorize” the downloading of the song onto another five computers.

Oh, gawd, I thought: 99 cents times 128 songs, and I’ll have to do it one by one. But it occurred to me that I probably didn’t even like half of those 128 songs any more. And after all, I was desperate: without this music, I kept telling myself, I would never again be able to exercise. And then I’d get fat. And I’d die. Egad!

Having learned, by now, to be cautious, I accepted the offer to re-purchase the first of the previously-purchased songs, and watched as iTunes went through its laborious process of logging me in via the Internet, authorizing the $0.99 charge on whatever credit card is associated with the account, and then signaling that the song was now re-authorized for use once again. Just to be sure, I then re-synched the iTunes library with my shiny new iPod — and, to my surprise, found that not just one, but all 128 previously-unauthorized songs, suddenly appeared on my iPod!

For all I know, I’m going to have a whopping charge on next month’s credit card bill. But at least I’ve got all of my music on a brand new iPod, which has lots of room to spare. And I’ve got my iTunes library on my laptop, which travels with me wherever I go. And I’ve got permission from Apple to spread that library onto five more computers, over the next few years. But most of all, I can exercise once again. So I won’t get fat. And I won’t die … at least not today.

Isn’t it wonderful how much more productive we’ve all become with all of this modern technology?