Lovely, I'm jealous. I used to spend my summers on Cape Cod, but now I live in Texas. How I miss Cape Cod!
I live in Mass and spend time each summer at Cape Cod and I find BARRELS of sea glass.
For Christmas, I just got a ton of plain serving trays and used some plaster of paris and I stuck the pieces on. They look gorgeous! I also did it with small gift boxes and made my own coasters (used some cookie cutters to shape)