Are you tired of all those identical yellow folders? Install MyFolder and pimp up the standard Windows file manager by customizing your folders' appearance. This program makes it easy and fun!
You can select the folder's new color either directly in MyFolder interface or by selecting the correspondent option in the folder's context menu. This second option is probably more comfortable, because when working from the interface you have to manually select each folder. I think this could be improved by allowing users to open several folders at the same time and then apply their chosen icons separately to each one of them.
The program includes a nice choice of new folder icons, including variations in color and also some special icons to mark folders as important, private, favourite and so on. The good thing is that you can add your own icons to the program's library.