Nerds have vastly different ideas of what constitutes celebrity compared with the creators of most T.V. programs. Cast in the nerd hero role are folk like scientists, inventors, mathematicians, spinners of stories, polymaths, explorers, individuals who push away at the boundaries of the possible.
A Venn diagram showing the sets of nerd heroes and of TV and other media celebrities would show very little overlap. For the record, what follows is a small celebration of a few great nerd heroes. It's not the sanest riddle, but I hope it entertains you for an hour or so ... and in the case of Sir Terry, your eyes may deceive you, be sure to use your ears instead ...