First was Celestia, who was interested in humanities technological advances. Particularly the radio. As it turns out, it did exist here, but it was only popular with nobility and some of the richer non-noble ponies in cities like Fillydelphia and Manehattan at the moment. When I told her that the radio had not only seen mass adoption, but had also been surpassed in popularity by TV and the internet back on Earth, that seemed to fascinate her even more.