Apparently the power went out last night (or more specifically, about two a.m.) during a thunderstorm because I had to reset the cable modem and restart my Mac when I woke up this morning. Normally everything just starts right back up. This morning, my Mac warned me that it was now December 31, 1969, which might cause some of my computer functions to behave erratically. That's an understatement right there if I ever saw one.
Darn, no wonder my internet connection wasn't working right. It hadn't really been invented yet!