there's a 'big halted' like shop in milpitas (not far away) called excess solutions. hint: bring a flashlight with you since there is very poor overhead lighting in that warehouse. it may be cold, too, as they leave the big garage doors open, so bring at least some kind of jacket. (strange to have to do all that to do shopping, lol)
it may be fun (for some) to drive around the google campus. its very close to the computer history museum on shoreline (exit on rt 101). one google building has all the android 'models' (jelly beans, eclaires, etc; all the android project names are there as large sculptures on one of the buildings and lots of tourists stop there to have their photo taken outside on the lawn).
at the end of the road on shoreline is the amphitheater park where there is a small body of water and you can rent paddle boards and canoes and have fun feeding the ducks
the drive along rt1 goes close to the pacific ocean and it can be a fun drive to start up north (just south of the city, san fran) and then drive south on rt1 toward santa cruz. you get some ocean/beach views and then some mountain road views.
if you like indian food, we have some of the best you can find
my favorite place is called 'sneha' and its a very large buffet (all you can eat) and people can usually find something there they like. highly recommended; and not too far from frys in sunnyvale.
monterey bay aquarium is world famous and worth going to. monterey (town) is somewhat touristy but still nice.
that's at least a few things that geeks can do in the bay area