There you can find information listenings about famous cities or famous people with their biographies as well as the transcripts, duration of the listening piece and worksheets to work with them
Two days ago Stephen Wolfram gave an early preview of his "computational knowledge engine" Wolfram Alpha at a talk at Harvard University.
The video of the whole presentation (1h 45min long) is here above, while down below you can find some highlights I transcripted from his speech.