You can have the strongest carbon steel Superman-Proof lock in the world, but if the rack you're attaching your bike to isn't secure....
Fritz from Commute By Bike calls our attention to this story from the University of Oregon, where three students had their bikes stolen when the entire rack was removed! The rack wasn't secured to anything, so it was apparently a fairly simple matter for the thief to (probably) drive up in a van or truck, load it all in, and speed off.
Man, it's not enough that we're now locking our bikes up with two or three locks, now we have to see if the rack itself is secure!
People, not speed.