IcoFX - IcoFX is an all-in-one solution for icon creation, extraction and editing.
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
RealWorld Icon Editor - Create Windows icons and Mac OS icons from images and 3D models in an integrated icon maker.
Sculptris - Sculptris: Enter a world of digital art without barriers.
IconLover - Icon editor for Windows.
ShapeShop - ShapeShop is an advanced and professional 3D design and modeling application that comes with an easy-to-use and user-friendly interface.