From Riccisoft and Alessandro Levi Montalcini:
Icon Tools is a contextual menu plug-in that lets you not only copy and paste icons via Control-click actions, but also customize your icons. After Icon Tools is installed, control-clicking on an icon will bring up three new options within the pop-up menu: Icon Tools, Icon Stamps, and Icon Frames. The Icon Tools option makes it possible for you to copy and paste icons, reset an icon to its original form, rotate or flip an icon, darken or lighten an icon, make an icon invisible, give an icon special effects, or make an icon's border more distinct. The Icon Stamps option offers 100 different ways to mark your icons. Icon Frames presents 30 backdrops for your icons. You can even put a single icon through many alterations and then designate it as the icon for several different folders. The Copy/Paste/Reset Icon commands can be placed in the main menu or in a subcategory, and Icon Stamps and folder, disk, and CD icons can be accurately positioned. Version 1.6 lets you create 8-bit icon masks with automatic methods or a drawing tool, show all of the icons in a selected file, turn all of a disk's custom icons on/off, updates icons in the Finder faster, and fixes a memory leak.