Sam's Walk
Sam Shah made a cool GeoGebra applet for doing a random walk governed by rolls on a six-sided die. He says: "The setup: You are on a hexagonal grid. You roll a dice and the # tells you which direction to move. If dice tells you to move to a hexagon you've visited, you stay at your old location, and roll again. You do 50 rolls. Let's see what happens!"
I haven't figured out how to stop the move if you've done it before, so in this sketch you move regardless. But the random walks are pretty interesting.
Hopefully Sam will blog about this, since his tweets are private!
(Sam's applet: you have to download it.)