bubbl.u

bubbl.us is a really neat online outlining tool. You can create an account (or just log in anonymously) and save all of your outlines.

The program allows you to print (with easy menu) your outline. Unfortunately, you can't save it as an image. However, if you'd like to save a copy as an image, it's easy enough to take a screenshot.

Of course, it's free (for now). It looks as if they are searching for advertisers, though.