I was driving home last night and thumbed through my iPod, trying to keep myself going even though my head was splitting. And there it was. Led Zeppelin’s “Stairway to Heaven.”

And I listened to it. I always listen to it.

There’s something about this song. I don’t know what it is, but it’s a song that no matter how often it plays, or how many times I’ve heard it in my life…I still have to listen.

Cutting it short is on the short-list of rock and roll sins I can’t commit (cutting short “Bohemian Rhapsody” and “Layla”–Derek and the Dominoes version–are close seconds). I don’t care if I’m at my destination, sitting in the parking lot with three minutes to go–I’m freaking listening to it.

And I’m not the only one. A friend walked into class five minutes late and the professor decided to ask his excuse for that. He said “Sorry, Stairway to Heaven was still going when I parked. I couldn’t turn it off yet.” My professor thought a moment and said “I’ll accept that.”

Stairway to Heaven is just one of those songs. It’s taken for granted how great it is.

And I sit there listening to the track, wondering why I can’t turn it off until it’s done.

Maybe it’s a personal quirk, but it’s a weird one shared by many people I know. And even though it gets louder and louder, it’s still turned up damned loud to start with. Wonderful.

I’ve read some pages that speculated about the song’s popularity. Something about the way the music starts soft and gets louder and more complicated. I suppose that could be a part of it. I just can’t get why just feels so good to put it on.

Honestly, is there some weird explanation for why this song works as a “must listen?” Is this just a Pavlovian response geared specifically toward classic rock fans? Is there some scientific mojo at work in this song, a crazy mathematical algorithm that was used to make this the “perfect” rock song?

I guess it’s just bugging the hell out of me that I can’t get it. I can’t get my fascination with it; I just have to listen.

Every single time.

And hell, I’ll admit when someone pointed me toward the video, I was watching Heart’s live cover of it for a week straight (and still do if I’m trying to get a bit emotional. I love the look on the band’s faces when they watch it from the balcony–looks an awful lot like delight).

Seriously, what is it about this song?

Any takers?