LineTracer

LineTracer is a tool for converting scanned hand-drawn sketches to vector format. It exports to EPS, which means the output can be used by about any drawing program. It is primarily meant for helping illustrators and animators.

This is one great, easy to use tool. I use it resize some of those patent images and still keep resolution. The cleaner your drawing or tracing the less fine tuning you will have to do after. Garbage in, garbage out.
This application doesn't install, it runs from it's own GUI. Remember where you put it because it won't show on your programs list. I have a folder named Tools for this type of application.
Shared by Johan Kotlinski on SourceForge.