Update: As of December 6, 2011 Write Comics seems to have gone offline. 🙁

Write Comics is a free, simple tool for creating comic strips. Write Comics doesn’t require any registration to use. In fact, registration is not even an option. To create a comic on Write Comics just select a background from the menu, choose some characters, and add some speech bubbles. You can continue adding frames until you’ve completed your story. Write Comics is quite easy to use, but there is one short-coming and that is the only way you can save your work is to save it to your local hard drive.

Applications for Education
Creating comics can be a good way to get reluctant writers to develop stories. Write Comics enables students who don’t think they’re good artists to create comics and focus on story development without worrying about their artist abilities.

Here are some related items that may be of interest to you:
Chogger – Create a Comic Strip
Create Your Own Super Hero Comic
Strip Generator – Drag and Drop Comic Creation