Post them into the greyness!
Treasuries:
Colorful Birds
Colorful Birds II
Macaws
Macaws II
Colorful animals
Colorful Animals II
Also do: Select your favorite color (it should be intense/light) to search for images that have it!
Examples:
Colorful Birds red
Colorful birds green - will show much nature as background, also fine to look at
Colorful Birds blue
Color Newgrounds!
3 ... 2 ... 1 ... GO!