Frico is a free icon maker app that can load jpg, bmp, png and gif files and create an icon file that includes smooth transparency for both Windows and Mac OS X in sizes ranging from 16x16 to 256x256 (for Windows) and 16x16 to 512x512 (for Mac). You can pick specific graphic files for a specific size, or load one general file for all sizes.
The program includes a preview of all the sizes your icon can be displayed at so that you can see the end result without fiddling with folder settings after you're done.
Frico can be run from the console and can as such be used as a part of a pipeline for creating icons. The console version supports all the same features as its UI counterpart.
Quick and easy generation of icon files without any distractions. The program is intentionally not an image editor as there are other far better tools for editing images but not so many tools for creating icons, at least not that are free. Frico supports both Windows and Mac OS X icons in all of the currently supported sizes. It also has console support.
Anyone who needs an icon, be it for their web page (favicon), software or any other circumstances where an icon is needed.