Icon Slate - Icon Slate lets you easily compose, import and export desktop icons in many formats.
Sketch Repo - Collection of resources for anyone who uses Sketch
Icon Generator - Icon Generator is a little application built on AIR that lets you generate a CS5 or Web 2.
Build with Sketch - Free LEGO-like kit for Sketch
IcoFX - IcoFX is an all-in-one solution for icon creation, extraction and editing.
IconXP - IconXP is an icon creator to edit icons. You can make icons for windows XP with this icon program.