First, with the crisis in Egypt where the government has shut down most internet and cell phone connections, Google has put out a Voice to Text Twitter service, so that the people on the ground can report on what's going on there. Wow.
Second, now you can tour museums with Google's Street View. If you start at the Hermitage Museum, you can see one of my favorite paintings of all time in its context: The Return of the Prodigal Son.