I just got a pair of neon blue gobies. The color is nice, they do well w/the coral, and best of all, they're cleaners. I've understand they do similar work to the cleaner wrasse and will clean other fish. So far, I've seen no cleaning, but the goby did try to suck on one of my percs yesterday. Mr. Clown wasn't having any part of that.
I also like the watchman goby and his buddy the pistol shrimp. Just gotta make sure your bottom rocks are firmly in the sand sitting on the bottom. Avalanches aren't a good thing as the pistol will tunnel.
I also agree about putting the mandarin off for quite some time.
"Life may not be the party we hoped for but while we are here we might as well dance!"