Brooklyn-based sandbenders EXOvault iPhone Cases made a big splash back in February when they first introduced these custom cases machined from solid billet aluminum and/or brass. They’ve expanded their product line since then to add fancy engraving and rosewood inlay, and their prices seem quite reasonable, starting at $110 for the basic aluminum model shown above and ranging up to $165 for the fancy engraved brass version.
These are not standing waves; they appear momentarily and then recede. Which is still pretty amazing. The machine, at Japan’s National Maritime Research Institute, is being described in the English-language blogosphere as having been designed to conduct water-safety tests. [via Neatorama]
Top 10 mechanical curiosities from the archives of Make: Online.
Turns out that the most useless machine (how-to coming up in MAKE Vol. 23) also makes a great cat toy! This Japanese version is sold as a bank that grabs a coin when you place it in the “bowl switch,” which is triggered by the cat in this video. [via Cute Overload]
Bicycle dynamos have been around forever. With all the DIY smartphone bike mounts I’ve come across lately, I’m surprised I haven’t seen someone attempt combining the two until now. This is perfect for areas with sparse charging options.
For those who aren’t up on their tradecraft, a “dead drop” is a place where spies or other clandestine-y folks drop off items for later retrieval by other agents. A “dead drop spike” is a particularly ingenious little container devised for the purpose. Basically, it’s a hollow metal spike, with a threaded watertight closure at the top. You put your top-secret microfilm or whatever inside the spike, take it to your dead drop, and stomp it into the ground with your foot. Then you cover it up with a rock or a piece of trash or whatever. The lid has a pull-loop built into it, so that when your contact comes by later to clear the drop, he or she can grab the spike by the loop and yank it out of the ground again.
Make: Online reader Baz from Dublin, ireland, sent us this rad video of a low-tech
self-propelled lawnmower that’s guided by wrapping a string around a couple of posts so it mows a spiral of lawn.
