Best rock song intros

What, nobody mentioned "Stairway"?

It's a good topic: the kind of songs that make you stop whatever you're doing and listen to the radio from the first note.

A few more candidates:

"Los Angeles," the first song on the first X album.

Just about every song on "Who's Next"

Prince was also good at this, in his early days: "1999" and "Let's Go Crazy" among others.

Midnight Oil, "Beds are Burning"

The Bangles, "Hero Takes A Fall" (a particular guilty pleasure of mine)

The Clash, "London Calling" (unless you're old school and prefer "White Riot"

Or, going way back, Chicago's "25 or 6 to 4" which was considered the coolest intro when I was a kid--I'm semi-embarassed to remember that the intro was our favorite thing to play in junior high school band!