Geico, a US car insurance company, has been airing TV commercials since 2004 featuring cavemen. Not living in the United States, I had never seen them before. They have a whole bunch of these ads running but quite frankly, not all of them are funny.
I will still include a short compilation of several of these ads below, just for those of you who have never seen them before. This video made my day!
Apparently, these TV commercials had a big success, at first. In 2007, ABC decided to produce and air a short TV sitcom featuring the cavemen but the bad ratings led the channel to discreetly cancel the show. The next series of commercials apparently focused on spoofing the unsuccessful TV series! Interesting way to bounce back after a flop...
Wikipedia article about the Geico Cavemen