Had that happen to me before with an old Dodge Omni I owned and somehow had managed to completely wear the brakes down on. It made for an interesting ride to work on the highway and various stop lights on the way. Trying to coast as much as possible to slow down, hoping to time the lights so I could slide through because stopping was NOT an option. After it was all said and done and the car was drivable again, the mechanic actually showed me the brake rotor. All that was left of the rotor was the center hub (where the bolts go through to mount it, in case you weren't aware). JUST the center hub, and maybe about 1/4 inch of a paper-thin sliver of "this is the part that's actually useful to the car" rotor. Which the mechanic flicked off while he was showing me. I'm still not sure whether to be proud or not of the fact that the mechanic said that this is the first time he's seen that in 20 years of working on cars.