In a TIBCO driveway in Palo Alto, CA, there's an 0.1-mile stretch with 8 speed bumps -- probably the most I've seen outside of a parking lot itself: https://goo.gl/maps/EJd2zis2otxYAj2N6
I had to do business there a few years ago and got into the habit of parking closest to the entrance and walking the rest.
Are there any other streets really enthusiastic about speed bumps?
There are two streets in my area that have speed bumps. Both in Saginaw Township, Golfview Drive has two and Shattuck Road west of Hospital Road has three. They are spaced a decent length from each other though.
County Route J2 on Tesla Road is awash with speed bumps East of Livermore approaching Corral Hollow Pass. J2 is an alternate route to I-580 over Altamont Pass and I guess the temporary solution to the safety issues is just to put down a shit load of rough speed bumps every mile or so. More of a highway than a street but nonetheless something I've never really seen replicated elsewhere.