I once again had my arm in my tank. I was pulling my "sand sifting star" off of a limpet (spelling?). All of the sudden my cleaner shrimp is on a rock getting closer. I thought hmmmm let's see if it will really do it.
Sure enough, it jumped on my hand. I called the wife over to look and she was looking at the rocks. I said look at my hand. She was impressed too. I let it stay until it got to my elbow, I started to pull my arm out and it jumped off.
The sensation was pretty cool.