Taco Bravo in Campbell, CA
This taco stand at 1950 Bascom Avenue is always popular in the evenings for post-drinking grub. Like Roberto's in San Diego and Taco Shack in Austin, it is more American than Mexican, but it still does the job with its cheap tacos, tostadas, burritos, frijoles, etc. The thinly shredded cheese, tasty hot sauce, and crunchy shells in particular keep me coming back here.
Honestly, I still prefer Roberto's over Taco Bravo as it is greasier (and hence tastier). But given that Roberto's is largely confined to the San Diego area, Taco Bravo will have to do for times spent up here.