Ayrton Senna's last duel with Alain Prost  Aug 23 2012

Alain Prost retired from F1 racing for the final time in 1993, with his last race coming at the Australian Grand Prix in November. He finished second in the race to his fierce rival Ayrton Senna but handily won the World Championship to the runner-up Senna. But the two of them raced for one final time in December of that year...driving go-karts.

Predictably, the pair took it very seriously: four-time world champion Prost having tested extensively before the event; Senna, a three-time title holder, having a kart shipped to Brazil so that he could practise.

Formula One cars are fast. Like super fast.  Jun 21 2012

Speaking of what fast looks like, here's a pair of synced videos that show just how fast F1 cars are. On the left are drivers participating in a track day, that is, normal folks who want to drive their cars fast on a real race course. A couple of them look like actual GT cars and are moving pretty quick. On the right, you've got F1 cars on the same track. It's not even close:

Here's an overlaid version and you can also see how much faster F1 cars are than just 25 years ago...the 2011 F1 car beats the 1986 F1 car by an amazing 22 seconds over a total time of a minute and a half. (via @coreyh)