I saw this on TV this evening and it made my inner geek very, very happy and made me laugh very, very hard. Brains FTW
It's a TV advert for a type of bottled water. It features Brains from the TV show Thunderbirds dancing around a stage. After a short while he goes and drinks some water and then returns to the stage dancing more and harder than before. I'd probably call it break dancing. It's definitely out of character but it's pretty funny. At the end of the advert he's on his knees with his arms in the air in a kind of big finish pose and the words "Brains perform best when they're hydrated" appear on screen.
The song is "Rhythm is a Dancer", which I think is by Snap? That makes me smile too because it reminds me of the early nineties and my first year at secondary school. We were based in the same building as the PE block and a lot of the time there would be gymnastic and dance clubs at lunchtime. The gym where these were held was right by the hall we ate lunch in and we would hear this song nearly every day.