"If you gaze long enough into an abyss, the abyss also gazes into you." That's Nietzsche. Having died in 1900, he didn't live quite long enough to see the PyottDesign Statial.b (via Hackaday), a mouse that can be adjusted in more ways than I thought possible. If he had, he might have instead said, "If you spend too long developing a completely adjustable mouse, stop."
What Nietzsche arguably meant by his abyss comment is that if you spend too long searching for meaning by contemplating an ultimately empty reality, watch out—because this could end up making you empty. This mouse makes me wonder along similar lines: if a mouse spends too long trying for a very human-usable design, might it not become too inhuman?
The answer, I think, is "no". Once you get past the shock of seeing it for the first time, it seems like it could be one of the most human-friendly designs around. It's just that, unfortunately, making such a genuinely useful flippy-turny-spready-upside-downy adjustable mouse means creating something that looks a bit weird.
Yes, it looks like a Razer DeathAdder that's been run over (and the initial reference design was, in fact, a 3D scan of a DeathAdder). And yes, it's a trypophobe's worst nightmare. But if you can get over those two facts, this freaky lil' thing is one of the coolest ergonomic projects I've seen in, well, possibly ever.
PyottDesign explains: "Modern grip styles have grown out of players adapting to standardized mouse shapes. The Statial.b lets new mouse shapes grow from grip styles." In other words, this well and truly puts personal ergonomic preferences first, not limiting your grip style in any way.
This means you can have it not just in fingertip, claw, palm, or vertical grip configuration, but anywhere between these things, for any kind of hand shape. It'd take me forever to explain all the different moving parts and the ways it can be adjusted, but thankfully the PyottDesign Statial.b product page has about a billion photos you can browse through at your leisure.
And did I mention it's open-source? You don't buy this thing, you make it. Which does, unfortunately, sound quite difficult. In the instructions (PDF) for the mouse, PyottDesign states that "knowledge of 3D printing, basic electronics and soldering skills as well as the ability to upload code to an Arduino are needed for this build."
If you have just such a collection of skills and equipment, as well as the time to devote to it, it might be worth a crack just to make a mouse that fits your hand just right. Oh, and to have something that can freak out your friends. That too.