The crabs are very cool because they are constantly foraging for food. They wrestle around. I put a hole nightcrawler in the tank and 5 crabs jump on it and rip it apart. One of the coolest feedings i have ever scene.
I have also thought about making a set up for Newts,frogs, water dragons, and anything that loves land and water. Its really important that you know what u want to put in it so the specifications can be made to that critter.
I am almost finished with my buddys crab tank. and will be posting pictures soon.