You will be suprised what all effects you can get by using the Layer Options(ie. Multiply, Hard light, etc.) That is how I got the sun effect on my avatar, well along with a lens flare, but it wouldn't have looked right without the layer options. And also how i got the Hachi Roku to look like it does on my webpage, on the top banner.
www.geocities.com/teamlonelydrivers/ that car was a fully colored pic and it changed just by one click of a button