We went over to our friends Dave and Cal's house for dinner tonight. After Cal's delicious baked meatballs and portobello ravioli, we tried out their new hot tub, on the back deck with a spectacular 180-degree view to the south--city lights, the bay, the ocean. As we enjoyed the evening air and clear sky, we spotted Jupiter and started talking about space, and eventually the current Space Shuttle mission and the fact that it is currently docked to the International Space Station. As we chatted, a bright star-like light appeared in the west and passed overhead. "Look, there's the space station now," I said, then laughed and added "I'm sure it's just an airplane."
When we got home I was checking the local newspaper online and saw an article saying the ISS was visible over the Bay area the next few nights. I went to the site they linked to, entered our location, and sure enough, it passed over right when we were in the hot tub and was really bright (magnitude -2.9).
We're going to watch for it tomorrow. Apparently after the shuttle undocks tomorrow night but while it's still adjacent to the ISS you will see them both, one behind the other.