JoJo2-Living in a coastal resort community which thrives on tourism and souveniers I can tell you one thing...
Don't over do it when being crafty with shells. You can end up with a really tacky piece of work if you're not careful.
As far as project with shells, I've seen shells on wreaths, planters, mirrors, napkin rings, jewelry, baskets, wind chimes, Christmas ornaments, candle holders...just about anything you can imagine.
The worst thing I think I've seen is seashell animals...I can't even describe how they form those shells in to everthing from frogs and turtles to elephants and giraffes. It is sad.
Edited for spelling...but I think I still missed some mistakes. My cold medicine is kicking in. 
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What if the Hokey Pokey really is what it's all about!?
[This message has been edited by CarolinaCarol (edited 01-29-2001).]