Let's get this out of the way with - I understand that on the roads, Jornet isn't even a sub-elite marathoner, but this is an interesting story nonetheless.
Ultra runner Kilian Jornet is attempting to summit Mount Everest in record time.
The background of the attempt is here -
According to his Facebook page, he is still waiting for the perfect weather conditions to start his summit, but it looks like the attempt will start soon.
Interestingly, daredevil Wim Hof made a very similar Everest summit attempt in 2007, and he was able to climb up to 24,000 feet in literally just his shorts. I haven't been able to find any information on how long it took him to do that, and without that info, it will be hard to compare his attempt to Jornet's.