I think question might need little more clarification. Is there any way to recuce screen brightness beyond what windows lets you except Monitor Birghtness Reducer?
I downloaded from here: http://download.cnet.com/Monitor-Brightness-Reducer/3000-2072_4-10690260.html?tag=bc
But it's using too much ram, even the developer accepts it in his readme.txt file i quote from the read me file, "**
... the second side effect is that this program will eat 15 MB of your RAM, just by starting it. This high memory usage is not a bug but it is by design.