If you own a Sony mirrorless camera, you probably know that an adapter can open up a veritable treasure trove of vintage lenses or allow you to use other manufacturers' current offerings. Of course, the one major drawback is that you often lose (or never had) autofocus in these situations. This neat adapter gives you back that ability.
Even though I'm a Canon guy, I'm also a glass geek, and the allure of sticking almost any lens (even from the 19th century) on a camera always has me eyeballing the Sony world longingly. That longing increased slightly when I saw this interesting adapter, the Fotodiox Pronto. It autofocuses manual focus lenses simply by moving them forward and backward, giving any lens you can mount on it the ability to autofocus, and maintaining the use of the camera's built-in image stabilization. There are a few catches: it can only support lenses up to 1.5 lbs, you'll need to add a second adapter to use something other than Leica M mount, and its use is suggested with 50mm or wider lenses, with telephoto lenses requiring a manual rough focus before the adapter takes over. I can't speak to the speed of the focusing, but if you're shooting portraits of the like with it, that shouldn't be a huge issue. It's certainly an interesting product that could be a nice addition to one's kit.