Saw something different up in the sky tonight. This time, it was an Iridium satellite. (Number 17, to be exact.) The Heavens Above site predicts their visibility, and pointed me to another page that tells all about the Iridium sats.
Basically, these sats have flat, aluminum-covered antennas that predictably reflect sunlight back to earth quite briefly and quite brightly. And with so many of them up there (90 or so), the reflected beams hit any given spot fairly often (a few times a week).
Brief (just a few seconds), but pretty cool.