I'm not always too clever about what to do with souvenir type things. I attribute that to the fact that we never vacation. Except last month. Anyway, my friend Jeri told me that many times they make cement stepping stones with their finds.
A couple nights ago, Jeff, Aidan and I made a stepping stone using a kit from Joann's and placed our seashells in it. It was pretty fun! It looks really neat as it is curing. The great thing is that the mold we bought can easily be reused in case we want to go on a vacation again in another 5 years.