Here's my sessile ctenophore shot. They are very common on sarcophytons, and I think should be in the guide. Most people just see the feathery feeding tentacles extended at night though, which would be much harder to photograph. This is about 1 inch long, and is on a retracted sarcophyton.
I have a quite a few hitchhiker pics but I'm not sure if the quality is good enough. I only have a video camera for digital pics so its hard to get close ups. I have included one of my clearer pics (the mantis shrimp, spearing variety) and a couple of not so clear ones (mystery snail and coral), I have many more of varying species so if they are decent enough I will send more.
I have a snail that has a shell that looks like stained glass.
And I have a "Green Thing" that has a white hard (calcium?) skeleton. When I first got the rock all that was visible was the skelton, months later it started to look like the picture.
I tried posting this pic in the newbie forum, but the file was too big. Hoping I can do it here. This urchin-like spikey thing popped out of my LR about a month after addition. It's the size of a penny. Any ideas?