So I'm parked on a NYC street (need to move the car tomorrow for street sweeping!), I go to move the car. Press the clutch and the pedal DROPS TO THE FLOOR and stays there. Pull it back up, it springs back, but if I press it, it drops back down.

The clutch doesn't disengage at all, and it was completely fine when I drove the car a few days ago.

What could be going on and how do I troubleshoot this thing? Seems to be a hydraulic clutch, but where exactly is the master cyl located? I've tried pumping the thing -- worked on a Saab I had with a dicey master -- but no joy here.