My weather loach likes to curl up, nose to tail, in the plants. Looks like a goof! He'll also charge around the tank, following the same path each time--over a rock going left to right, then under it on the right to left trip.
My betta will swim part way through a hole in some drift wood, and then hang there for a few minutes.
My eel loves to curl around the other fish. My upside down cats are the only ones that will tolerate this, so he tracks one down and wraps himself around it. The cats put up with it for a few minutes, then go find another hiding place.
In the SW tank--the engineer goby is shy but curious. He'll slither away when you first approach the tank, then peek out and watch you. If he thinks you can see him, he ducks back and comes out someplace else.
We have hermit crabs that will hitch hike on some of the larger snails--they panic once the snails gets very far up the glass, and usually end up falling off.
