There's lots of reasons why we can't have nice things; when it comes to bicycles, it's because arseholes enjoy stripping them for parts, or stealing them outright. This project is trying to fix that, one oddly-shaped magnet at a time. The concept behind Hexlox is reasonably simple: it's a piece that uses a magnet to sit in the head of a hex-head bolt, which are used all over bikes to lock components in place. It's a weird shape, preventing it being extracted by pliers, and magnetically shielded so that only the owner, with a unique key, can extract it and undo the bolt.
Yes, security skewers already exist for wheels, seatposts and saddles. But they don't work on every design of bolt, and they're also so ubiquitous that thieves carry keys to most of the common brands. Hexlox will work with any steel hex bolts, and is supposedly much harder to pick.
I don't believe that they would defeat every would-be scumbag, but the novelty of the solution would probably scare off most casual thieves, which is what you really want — if someone armed with an angle grinder wants your bike, there's not much you can really do about it.
Of course, the usual crowdfunding caveats apply — untested product from an untested company, so there's a decent chance what you're promised will never show up. But for €21 ($31), I'm willing to take a chance on protecting my wheels.