"Paint.NET is image and photo manipulation software designed to be used on computers that run Windows XP...Paint.NET has many of the powerful features that expensive commercial applications have, including the ability to use layers. This is the second semester that Paint.NET has been a project at Washington State University, and we have the goal of adding as much functionality as expensive commercial applications provide, but of course, for free! In the spirit of all this freedom, we welcome any suggestions, as well as provide the source code free of charge for anyone who wishes to tinker with it. Please explore this website, download the software and try out many of the things you would do on those expensive commercial applications."It might bear the humble name of "Paint", but add the .Net on there and you actually have a decently functional application! It's free, and you only need to have the .Net framework installed (which you can get free from Microsoft). This is the kind of thing I'm going to carry with me on my Verbatim USB Flash drive in case I'm at a PC that lacks an image editor.