I've been thinking of better ways to do programming tutorials and something like this is roughly what I had in mind. Thanks for open sourcing it!
http://www.storytellersoftware.com
Everything is stored locally and the tool can generate an HTML playback file that can be passed around. One can also make comments during the playback. There tends not to be a great place to document how code evolves, we think a playback is the best place for this.
Its not quite ready for prime time yet but it will be soon. Our long term goals are to make a web app to store playbacks and to make it the next generation of version control.