You can choose your own backgrounds to liven up your folders
The procedure is really simple: Just navigate to the folder that you want to decorate and click Edit > Backgrounds and Emblems. You can then choose whether to have a pattern or colour and you can even pick your own image. Just drag the icon into the folder and the background will change.
This menu also has a useful feature of adding emblems to files and folders. You can use these to highlight important files and make then stand out by dragging the emblem onto it. To reset the emblem, just drag it on again.