Google launched Hot trends, which can track search queries. It provides a list of top 100 search terms, updated several times a day.
A lot of people have already written about it, still I am missing the part about how people can explore this data.
I can see domainers using the hot trends to register domains on the fly. Also fast online marketers and SEOs can probably pull some nice traffic out of this. For myself Hot trends is pretty useless.