Got to put my backup plan into action today. Just as I arrived at work, the rear axle sheared when I was jumping a curb leaving my rear wheel unusable. One of the few good things about working where I do is that within walking distance is a bike shop, so after work I walked over there with the axle. They didn't have a replacement with the correct threading, so back I walked, just in time to grab my bags from my office and make it to the bus stop with 1 minute to spare. Bus was on time and dropped me off 5 blocks from my house. While the ride in was great, the bus ride and walk home took 15 minutes longer than cycling, and I got to see all the bus people.
In the 3 years I've been commuting by bike (on and off), this was only the second time I couldn't ride home due to mechanical failure. One other time, I stayed very late, until 1 AM and asked a coworker to drop me off at home.
Hope the humidity drops some time soon!