Excerpt:
The Flintstone House is a free-form, single-family residence in Hillsborough, California[1] overlooking, and best seen from the Eugene A. Doran Memorial Bridge on Interstate 280.[2][3] It was designed by architect William Nicholson and built in 1976 as an experiment in new building materials, in the form of a series of domes. It was constructed by spraying shotcrete onto steel rebar and wire mesh frames over inflated balloons. Originally off-white in color, it was repainted a deep orange in the mid-2000s. The house contains three bedrooms and two bathrooms.
Known popularly as “The Flintstone House”, it derives its name from The Flintstones, a 
Hanna-Barbera Productions animated cartoon series of the early 1960s about a Stone Age family.
My comment: it is very strange in an upscale neighborhood, visible from the freeway. I don’t think the neighbors like it ;>
Link to Wikepedia: http://en.wikipedia.org/wiki/The_Flintstone_House
This is the coolest. Every time I hear about fieldstone homes it totally makes me want to have a house like this one.
I think Highest and Best Use will eventually win, and that site will become a Hillsborough estate. If it was in an outlying area in the desert HBU as is would be to leave it alone. As if vacant it certainly wouldn’t be to build that. It looks like a large lot, and is probably worth a million or two or more in Hillsborough. Next time on market it’ll likely receive interest and offers as a home site, not as the Flintstone Home.