I was actually thinking of an invention during a range in Grafenwohr. It seems feasible enough, and I personally think it will be invented in the next thirty years. Remember I'm going for practical and creative here.

My invention is a pair of sunglasses. Of course they aren't just any sunglasses, they are meant to block UV rays better than any other sunglasses. For starters, the shading of the lenses is adjustable. That's not all, however. Have you ever looked in the direction of the sun and covered it with your finger? Well that's the idea behind these glasses. When you wear the glasses, wherever you look, there is a black spot covering where the sun is in your vision. The black spot is adjustable from nonexistent to twice the radius of the sun in your vision. The black spot could even be an image of a sun for cosmetic effect. This would create 99.99% glare reduction. I've given some thought to a few theoretical ways these glasses would work. For any of you that have ever fired toward or observed a point in the distance in the direction of an evening sun, the application of such a pair of sunglasses is instantly obvious. I know most of you don't see the sun much, not leaving the house and all...