I just moved my coastal into a 4x2x2, and now i have an empty 20G long glass aquarium.

Obviously this means it is time to plan what to get next for my collection!!

At the moment I'm giving serious consideration of making a divider for the cage and picking up two mexican hognose snakes to house in it.

However, I'm giving you guys a chance to give me some other suggestions before I commit to anything.

So, what would you guys put in there? Don't necessarily limit your suggestions to snakes or even reptiles, I'm open to any pets that do well in a 20G long.