add-on to change gamma settings

[acemaxx]

I was wondering if there is an add-on out there that would allow you to set a keybinding for raising and lowing gamma settings?

I noticed today, when I was in a very bright zone, that it was very hard to see my target ring and tell which mob I had targeted. I thought it would be nice if there was a quick way to change the gamma settings, with out going through the Video options.

Or, instead, it there is a way to change the color of the target ring, so it doesn't blend into the background.

Just a couple thoughts. I don't even know if they are possible