Before Dawn is a an open-source, cross-platform screensaver application using web-based technologies. You can generate screensavers with it using HTML/CSS, javascript, canvas, and any tools that rely on those technologies. In theory, generating a Before Dawn screensaver is as simple as writing an HTML page.

The project developed out of a personal project to explore the history of early screensavers. I decided that I wanted to write a framework that I could use to actually run screensavers on my computer. I wanted it to be cross-platform and easily accessible to artists and developers.

Before Dawn is definitely a bit of a experiment -- to actually use it, you need to run it as a separate application on your computer and disable whatever screensaver you have running in your OS, but it is fun and definitely works.