IcoFX - IcoFX is an all-in-one solution for icon creation, extraction and editing.
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
RealWorld Icon Editor - Create Windows icons and Mac OS icons from images and 3D models in an integrated icon maker.
Grafx2 - GrafX2 is a bitmap paint program inspired by the Amiga programs Deluxe Paint and Brilliance.
IconLover - Icon editor for Windows.
Piskel - Piskel is a website where designers online create sprites or pixel art.