I love that song by Radiohead, I wanted it for my iPod, and I simply assumed I could download it at the iTunes store. No such luck--they don't carry anything older than the band's new In Rainbows album.

Next stop, Amazon. I was excited to see the song listed, only to find it was only available by downloading the entire album. I even checked Yahoo! Music, but it looked like I would have to sign up for their monthly subscription service. Way too complicated for just one track. And not to sound self-righteous, but I couldn't even begin to consider a file-sharing site.

Oh yes, I did have one other online option--downloading a version by the "Radiohead Tribute" band. Right. Can we say Beatlemania?

So the next time I was in Borders, I wandered over to the Radiohead bin and found the CD with the song. I stood transfixed, holding the CD and waiting for something--a critic's blurb ("Best Album Ever!"), divine intervention, a message from my gut--to convince me to take the plunge and buy the entire album on the basis of a single song.

I couldn't do it. I couldn't bring myself to spend $13.99 for a song I coveted. I was frustrated. If I had been a few (okay, many) years (okay, decades) younger, I might have thrown myself on the floor and thrown a temper tantrum.

After calming myself, I began to realize that I was in the exact same situation as people I've spoken to in focus groups, people who have all but abandoned CDs. Why buy an entire CD when you might only like a couple of songs, and when an alternative acquisition method is readily available (downloading individual tracks, legally or illegally)?

Then my somewhat obsessive habit of thinking of the broader implications of seemingly insignificant situations kicked in (a habit, by the way, that can be a blessing in one's professional life but a curse in one's personal life).

On the one hand, my experience spoke to some of the well-documented benefits of the Internet: convenience, ease, 24/7 availability, instant gratification. But in my mind, something broader, more profound seemed to be going on.

Not too long ago, the very notion of acquiring an individual song would have been unthinkable (unless the song happened to be released as a single). I would have had just two choices--buy the album, or live the rest of your life "Karma Police"-less. And even though I'm in that state right now, I realize that's more and more becoming the exception. If I had been looking for a different Radiohead song, or if I didn't feel guilty about file-sharing, I could very well be listening to Thom Yorke as I type this.

What seems to be happening is that the world of commerce is shifting from prix fixe to a la carte, from needing to buy the complete package to picking and choosing just the items one wants. The music industry, historically structured in prix fixe (i.e., complete albums) terms, has been one of the first to feel the effects of this shift. But the media industry is feeling it as well. (Why subscribe to a newspaper when I can pick just the stories I'm interested in online?) And we're already seeing the beginnings of the shift in the television industry, where people can download individual programs whenever they want, without needing cable or satellite TV--or a TV at all, for that matter.

What's most significant in all of this is that it's more than just a shift in the primary transactional unit. That's happening, for sure, but it's being accompanied by a more profound shift in the consumer mindset. From "I guess the companies know what's best for me, so I should accept it," to "I know what's best for me, so you'd better adapt to it."

Think of magazines, which strive hard every issue to include a range of material that readers will find interesting and that adds value. But hey, we all know magazine subscription is shrinking. Why? Because it's faster and more convenient to read stories online? Maybe. But I think it's because the notion that an editor knows what's best for me is fading fast. Empowered by the vast choices offered by the Internet, consumers are becoming accustomed to making those choices for themselves.

Some industries have already embraced the new a la carte environment--for years now, the computer and auto industries have been allowing consumers to "build their own" machines online, choosing just the features they want. Other industries may be immune--industries where the product's piece-parts hang together as a creative, coherent whole. (It's tough to imagine people buying only a chapter of a book or a scene from a movie.)

On the other hand, the shift is probably going to wreak even more havoc in other industries, like television delivery. The whole a la carte channel debate is likely to intensify--why should I pay for a package of 75 channels when I only watch five of them? Or even, why should I pay a monthly subscription for a premium channel when I only watch a handful of its programs and shows?

Are product bundles an exception here (e.g., "triple play" offers of telephone, Internet, and TV from a single provider)? To me, that's a different animal. Consumers want or need those three things, so they may as well get them cheaper (bundled discounting) or easier (single bill). But throw in things consumers don't want--the price is higher, but you also get Yak Recipes Illustrated every month--and you kill the whole concept.

There will undoubtedly always be consumers who consider those responsible for producing a product to be experts, and as such have the best idea of what would be useful and valuable. But I've got to believe this is a shrinking population, to be replaced by younger consumers who, every day, have the luxury, and freedom, to choose from a myriad of options online. More than ever, companies will need to move from wondering, "How do I convince people to buy what I've got?" to, "How can we make sure we give people exactly what they want?"

The Internet is spoiling us. Me included. I'm holding off on "Karma Police" until I can buy it, legally, as an individual download. If you happen to know where I can find it, let me know (just don't send me the song, please).