Seasons

I ran across a pretty interesting interactive visualization that explains why we have seasons and how they would change if the Earth had a different tilt.
This interactive lets you examine the main factors that affect temperature: the position of the Earth in its orbit around the Sun, the tilt of Earth's axis of rotation, and the path of the Sun in the sky over the course of the day. This visualization enables you to look for connections between these factors and the average temperature over the course of the year.

It doesn't closely follow Tufte's principles (distances and sizes are not to scale), but I think that it is negligible, considering the goal of the authors of this visualization. It does, however, represent a lot of information in a way that we can take it all in.

http://highered.mcgraw-hill.com/sites/007299181x/student_view0/chapter2/seasons_interactive.html