Holy cow! You, my new best friend, have inadvertently been given a key to the Cupertino campus. Dress corporate casual, go there, and check on His Jobsness' progress with the new ACDs and tablet.
Seriously, that's a kick-awesome key. I don't know what it's to, but if you don't need it, how much do you want for it?
It's the old key to the RDF generator control panel......
which has long since been upgraded to the 60Thz/84x dynamically symmetrical-core matrix-based Ultra-Super-Grande Mac Pro, which only Steve knows how to log onto