If you haven’t spent some time checking out one of Lori’s great nature programs exploring the tidepools, you should be sure to do so. Some of the best tidepools right now are during low tide at the South End of the beach. (Take Huyler House walk and turn right.) We have found great treasures in and around them recently. Check out this incredible cone of sand, exactly one grain of sand thick, and absolutely beautifully constructed.. it looks like a mosaic! 
I had never seen it before, so I sent it the the incredible naturalists in the Charleston County Park system. They were the instructors for my master naturalist class, which I HIGHLY recommend for anyone who wants to understand more about the incredible creatures and intricate relationships of the incredible beaches, forests, and marshes in our areas. It didn’t take long for Rachel Herold to get back to me with the scientific name, Cistinedes gouldii, aka Pectinaria Gouldii, the ice cream cone worm. According to the Rhode Island Sea Grant Consortium,
The low tides that lay bare the sandy expanses of the tidal flats give this extraordinary animal its habitat. Here, exposed for a brief time until the next rising tide, a shell remarkably like an ice cream cone can be found. Less than two inches long, it is composed of sand grains neatly fashioned and glued into a mosaic of artistic precision. Because the shell is made form the very sand on which it lives, it usually escapes notice.
This artifact is the domicile of a worm related to the earthworm, but more closely to the clam worm Neris Virens so highly prized as bait by fishermen. It belongs to the class Polychaeta, meaning “many bristles.”
The trumpet worm has also been given the scientific name Pectinaria gloudi, “pectinaria” referring to the sharp bristles that form the golden combs used to sift the sand for food. While seemingly fragile, these body parts have amazing strength and are used much like the blades of a bulldozer.
One of my favorite field guides is Seashore Animals of the Southeast, which says that the worm
feeds below the surface of the sand on deposited organic material. The tube is open at both ends.
You can see a photo of what the worm looks like here. It looks like I am not the only fan: for reasons that completely escape me, this worm even has a facebook page.
And, in a case of knowing just what to look for, Lori sent me a note that she found a complete one of these just after Irene, on the IOP beach. She said the tentacles that protruded from the cone were gold.
http://www.sms.si.edu/irlspec/Pectinaria_gouldii.htm
http://seagrant.gso.uri.edu/factsheets/trumpet_worm.html
http://www.mitchellspublications.com/guides/shells/articles/0099/