Okay, this a little bit of a cheat. Every morning I've gone to the beach early enough I've ended up with photos of crab tracks, including this morning, but my favorite of them was from a few days ago. I like the patterns.

These are small crabs, sand colored and more boxy than round. When the sun is going down their shadow looks like Batman. Before 5am, the beach is laced with these tracks. After 5am, they're mostly wiped away by people.