Algodoo

Simple fractal with simple scale indicator to the left.
Only 3-4 iterations because of limitations with how many polygons can be shown in before it gives out of memory errors

A way to bypass this and make it easier to render would be to take many separate gears layered on top of each other but that would take a lot more effort to get it set up

ps. low end computers might take a long time to load the scene
but its a neat concept.

I just used the gear tool and gearify tool on an existing gear and decreased the gear tooth size by 1/4 each time.