A couple of people at New APPS have suggested "Sister Ray" by the Velvet Underground, a droning, hypnotic account of banal debauchery. It's good, but a bit too obviously experimental. "Roadrunner" is based on it, but much happier. Jonathan Richman takes the Velvet Underground's reversal of the usual '60s themes ("I'm sick of trees, take me to the city" and the taunting "all you protest kids") and embraces their more positive implication: "Doesn't anyone love the dark? And Route 128 out by the industrial park?" He loves driving around at night with the radio on. It's not postmodern irony but love. Which perhaps disqualifies it as punk rock. More appropriate might be something that runs on anger, like the live version of "Boss Hoss" by the Barracudas. I don't know the story behind this recording, but I think the Barracudas were supporting the Stray Cats, and were about as popular as supporting acts usually are. Here they're clearly having some technical problems, and it sounds as though the crowd decides to make things worse rather than wait any longer for them to get their act together. I'm probably imagining things, but I've always felt as though the song becomes an expression of pure frustration, or a pure expression of frustration. Which makes it sound great to my ears, but it's not universally hailed as a classic, and there's probably a reason for that.
The best rock song of all time is the one you're listening to right now, as long as it amazes you with how good it is. There are lots of perfect songs ("Crash" comes to mind), so any of those that you haven't heard for a while (e.g., for me, "Cool Guitar Boy" when it came on while I was driving the other day) would be it. But if you want something more definite it probably has to be Iggy Pop, either "The Passenger," which claims triumphant ownership of the entire world, or "Search and Destroy," which combines violent fantasy ("I'm a street-walking cheetah with a heart full of napalm"), self-pity ("I am the world's forgotten boy"), lust ("love in the middle of a fire-fight") and poetic nonsense ("I'm the runaway son of a nuclear A-bomb") into something as close to the ultimate punk rock song as you can possibly get.