Originally Posted by balto charlie

Can opener, like the idea, small ultralite.
Tennis ball< can't picture it working. My locker has a key/tumbler in a handle. When closed the handle is pushed in and is flush with the door. Covering with tape might work. If I am organized that is what I will try.

So yesterday, armed with all of the aforementioned supplies, I took on the door. Due to mother nature thawing the lock, handle and door all worked flawlessly. I think it knew what I had in mind(especially the hammer) so it surrendered my bike. Since I was armed to the hilt I liberally sprayed the lock and handle with ethanol, waited for it to evaporate the applied the Boeshield T-9 and WD-40 to the various moving parts, tumbled, and handle components. This morning it moved like silk.
MORAL OF THE STORY: preventive maintenance goes a long way. Plus I am now carrying a small bottle of ethanol and a large friggin' hammer
Thanks for all the advice folks. Stay warm, things are rather chilly these days