IrfanView - IrfanView ... one of the most popular viewers worldwide.
Faviconer - Faviconer.com, or favicon generator, is online tool for creating favicon.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
ConvertIcon! - Converticon is a simple icon utility.
FastStone Image Viewer - FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor.
Ordinatore - Those who want to tidy up their Macs will surely love this application.