The OSX alternative is Seashore. It's got the same goal as Paint.Net, to be a simple and easy to use image editor and is based on gimp, so it's stable and suppo

The OSX alternative is Seashore. It's got the same goal as Paint.Net, to be a simple and easy to use image editor and is based on gimp, so it's stable and supports many things. I'm not sure there's a similar project for Linux.