Editor: This free program allows you to change the screen brightness (gamma) by pressing hot keys - Win+Up and Win+Down, from anywhere, even from within most games.
Unzip it MammaGamma.zip into any directory and run it.
TransXP (part of MammaGamma) allows you to make any WinXP window transparent. Move the mouse to the windows鈥檚 title and press Win_Left or Win+Right.