Radiohead B-side to the various Pyramid Song singles; released around the world in May of 2001.
The song is actually composed of two distinct sections:

The first half (up until 1:34) is a raucous, noisy rock song in the tradition of Paranoid Android and Electioneering, with a good deal of Pro Tools processing added to keep it well within the bounds of the current "Radiohead sound."

The music begins with a burst of noise composed from digitally messed-up samples of later parts of the song, and then the bass guitar comes in playing a wicked riff in the key of D minor. The percussion sounds like live drumming, probably Phil Selway playing a funky bass/snare pattern along with straight quarter notes on the ride cymbal. The electronic noise continues in the form of a synthesizer oscillating around, and there is someone making weird singing/squeaking noises that have to be a tribute to (if not a sample of) the Pink Floyd's Several Species of Small Furry Animals Gathered Together and Grooving with a Pict.

Thom sarcastically snarls and sneers his vocals, and when he gets to "I don't know what it means" a huge ensemble of guitars and electronically-processed noise (some of it sounds like a tape being eated by a tape player, sped up to ludicrous speed) comes in playing a riff similar to the bass line.

A distorted electic guitar continues playing a variation on the same D minor riff and some of the noise recedes while Thom comes back in with the next verse. When he sings "the end of the tunnel" for the last time the noise-chorus comes back in, growing faster, louder, and higher in pitch while someone chants "You better start naming names" and the guitars noodle crazily until the whole mess hits a musical brick wall and aurally explodes into little pieces with the sound of a cruise missile jarring a needle off the record it was playing.

It's that good.

The second half of the song rises out of the ashes of the first in the form of dreary, plodding synthesizer chords that sound as though they have been articulated with human vocals, possibly via a vocoder. It is an extremely eerie feeling to listen to a synth attempt to speak to you with very slow and indistinct syllables.

As for the lyrics, your guess is as good as mine. The song could possibly be about Thom Yorke's coming to grips with his status as an international celebrity and political activist. "I don't know what it means" could refer a guy like him being followed by the gossip columns in various magazines, his response to interviewers' questions about his lyrics, or life itself.

The phrase "trans-atlantic drawl" could refer either to the way people who constantly jet from the U.S. to the U.K. and back speak, or to an oxymoron: "Trans-atlantic" connotes cultured, rich businesspeople, while "drawl" is the way hicks from the Southern and Western United States speak. Maybe a veiled reference to George W. Bush?

The line about "the light at the end of the tunnel" has been quoted several times on the band's official site (radiohead.com); it refers to a conversation between CNN correspondent Christiane Amanpour and the Iraqi Deputy Prime Minister, Mr. Tareq Aziz at a press conference on November 12, 1998

CNN: But sir, isn't it true that many of them have expressed dismay or at the very least surprise that at this very moment, when it appeared that there was the light at the end of the tunnel that you had so long asked for, at this moment, you chose to break cooperation with UNSCOM? And that's -- they can't understand, they say.

Mr. Aziz: We don't see any light at the end of the tunnel, Christiane. With all respect to them, they haven't shown us -- nobody has shown us a light at the end of the tunnel. There is a tunnel after the tunnel.

Correct lyrics:

I was born for your magazines
For your magazines
I am trapped in the society page
Of your magazines
Of your magazines
I don't know what it means

Do you see the light at the end of the tunnel?
At the end of the tunnel?
Do you see the light at the end of the tunnel?
At the end of the tunnel?
At the end of the tunnel?

You better start naming names