I would make an argument for Bill Gates. I know on HN people might snub this, but I honestly believe that for better or worse, the future was reshaped by his business tenacity.

I know that everyone involved in the entire PC movement equally played a big part, but Windows ended up being the huge unifying factor for Joe White-Collar-Worker. I think the surge in office computing in Windows was what eventually lead to the acceptance and idea of "normal people" owning computers in the home and consequently the drive towards intelligent consumer electronics in general.

Also a mention for Sir. Tim Berners-Lee, of course it was not a one man effort but he is largely attributed to the creation of the WWW which, let's face it, has already hugely reshaped society in many ways.