HackerMaker

Markus Kayser uses Sahara sun to sinter (melt and fuse) sand in a layered technique like 3D printing to produce glass objects. He gives a talk and explanation in his TEDx talk. If you subscribe to his YouTube channel , you will see his other sun-cutter video. In Bang Goes the Theory  these guys use focused sunlight to melt rock at 3,500 Celsius: "Just two square metres of sunlight can melt steel easily"

Chris Notap shows how to cut through glass and ceramics with cheap diamond hole cutters from ebay, and shows a nifty pop-bottle water feeder for cooling the bit, as well as a simple jig to hold the drill steady as you start a new hole.

Rulof Maker is always good to watch. Here, instead of repairing some plastic spectacle frames, he makes some out of wood. What is quite amazing is the good results he gets without measuring, and using a thick felt pen to draw outlines with. What is even more amazing is how he doesn't lose a finger while doing it! If you want to buy some nice wooden sunglasses (which I presume he didn't make, follow the link:  https://goo.gl/BNWcfQ  which probably contains his Amazon partner ID)