Well, it seems I was the victim of some Halloween mischeif.  The air was let out of my left, front tire.  I have not yet determined the cause, but noticed when I attempted to back down the driveway.  My guess is that someone propped a nail up behind the tire, since this happened to Becky's car a few years ago while we were in the apartment.  It was pouring rain this morning, so I got a ride to work rather than get all nasty in the rain and have to get ready all over again.

This evening, I'll put on my spare donut and take it in to see what is the trouble.  Hopefully, it will be covered by hazard insurance, although it probably won't be that expensive.