Last night I played with code swarm and generated a short movie depicting the history of the HelenOS project repository in 230 seconds. The video below utilizes four frames per day. I have obtained slightly different results with one frame per day and also eight frames per day, but this one seems to be the best.
Things get interesting around the times when there was a HelenOS camp and also when people worked intensively on a branch as part of their University assignment.
Update: Here are download links for the one-frame-per-day video, four-frames-per-day video and eight-frames-per-day video.