In fact, the best thing is: Free art in the form of all the seashells you can carry home in the bottom of a tote bag full of sand and wet towels.
Check out this grouping that hangs in my bathroom. I took six picture frames and glued a shell to each, on the outside of the glass.
You could do the same with interesting rocks or bits of sea glass.
I also tossed some in a wooden box in the family room that keeps the remotes in check.
You can glue a collection into an old printer's tray and use it like you would a print or a painting, like I did in my family room.
Or you can use them to in your patio, deck or garden decorating...
You wouldn't want to overdo it, though. It's too late for me... Save yourself.