Via Gizmodo, more details there.
The one depicted is the X-35 [the prototype that won the contract for the Joint Strike Fighter and became the F-35]. I don’t know who posted it on YouTube, but the level of NDA’s was substantial where we were not even allowed to showcase it on our demo reel.
The above looks like CGI though (not real footage), unlike the one below:
According to a friend, the problem with the vertical takeoff is exhaust. The engine tends to stall since there's no oxygen to draw in, so they need special absorbing landing pads.