For a time, I was thinking of concepts for glasses that adjusted the way the wearer sees the environment.
Although my concept was way more intense. With levels and curve adjustments for a few of us who are OC about the surroundings, (And for those hardcore gamers who enjoy their regular dose of eye candy) the Gunnar is a dream come true.
The picture below is myself, sporting a borrowed pair of the back frame version. It's very sleek, and hugs the face just right. And quite actually it's pretty light. You'd hardly feel it on your face. It also doesn't look half bad. But I wouldn't recommend it as a replacement for your graded glasses.
I'm not a huge fan of tinted glasses for normal wear. But the overall effect is more than enough.
How to get one: