If this house evokes memories of The Flintstones, you're probably not alone. When a rotary spray gun for cement was invented in the 1970s, architect William Nicholson decided to try something new: He inflated aeronautical balloons, then sprayed them with cement. There was one major setback: Someone on the job didn't watch the weather forecast that day. A heavy rain after the first spraying led to a collapse of the original structure. According to locals, the house was originally off-white; the owners painted it a loud orange, making it stand out all the more. Like many wild houses, some neighbors thought the building was an eyesore. This one was even reported to the Hillsborough neighborhood's architectural review board. But to many others, it'll always be fondly known as the Flintstone House.