There aren't many cool robot videos out right now. So I'm gonna reach into a completely different bag of tricks. I want to show you a video I found not too long ago demonstrating a welding technique called Friction Welding. I didn't know that this type of welding existed until I found some videos showing it.
Basically what happens is they take two pipes or round shafts, put one in a stationary chuck and put the other in a rotating chuck. They get the rotating shaft going very fast, then they jam them together. The friction between the two shafts causes the metal to melt and creates a perfect, seamless connection between the two pieces. It's pretty cool. And don't worry; there are some industrial robots in the videos.