Pixelformer is a bitmap graphics editor, specifically optimized for creating and modifying small-sized images, such as icons, avatars, buttons, etc.
It does not restrict you with a limited tool set specific to classic icon editors. Using Pixelformer, you can work with images of any size and with files of different types (including BMP, PNG, PSD, TGA, JPEG, ICO, and CUR files, as well as EXE, DLL, or ICL), use semi-transparent colors, compose your icons with multiple layers, make smooth antialiased images using the power of supersampling, dynamically generate highly optimized palettes, and save the results in a desired format. It also includes a PNG optimizer which losslessly minimizes size of PNG files and Vista icons.