Come ride the waves with not_the_water's great post about slab surfing
bassomatic says, "my dad and his team of underwater archaeologists were the first to find an ancient shipwreck using side-scan sonar..."
Scary stories and freaky facts about oxygen deprivation at altitude
AskMe offers some resources on cloudwatching for beginners
Moby Dick is fabulous - Mefites talk Melville and subtext, and what you thought of classic novels before you read them, and the linked writer drops by to respond
Submersible finds glowy purple orb in the depths
And finally, that pressing question, what if I fell out of an airplane in a tank full of water?
We don't know for certain if the Gas! GAS! in Wilfred Owen's devastating poem was chlorine, but we do know that it can kill and maim in the way he described. But when his poem was written, chlorine had already begun to play a completely different, quietly heroic role, going on to save hundreds of millions of lives over the course of the 20th century.
Check out clawsoon's great, in-depth post "Chlorine probably saved your life today"
JoeZydeco on how a vending machine knows what coin you've put in (and why the Mars candy company spun off an electronics company)
codacorolla on their academic research on Minecraft players
The evolution of thimble technology, as seen in artifacts found scattered across England
A nice discussion of the importance of the skills needed to maintain old systems