Well, the site doesn't say how or with what, but it does look like it's done with sea glass and wouldn't it be cool to try to do this?!
Coastal / Cottage Decor, Children Room Decoration, Driftwood Boat on Canvas, Beach House Decor. $35.00, via Etsy.
Sign of Sea Life: Octopus (kracken). Sea glass [beach glass] , natural wood background, pallet sign
Sea glass and pebble art by sharon nowlan 8 by 10 by PebbleArt
Grey Wood Art Fish School Sign Wall Decor Beach by CastawaysHall
Make your own frosted beach glass out of recyled bottles ... Tutorial
Sign of Sea Life Medium Sea Glass Beach Glass Seahorse by SignsOf, $40.00
DISTINCTIVE SEA GLASS SAILBOAT PENDANT CREATED BY ARTIST GEOFFREY M. GOODMAN USING ONLY GENUINE CHESAPEAKE BAY SEA GLASS AND DRIFTWOOD. (ALSO
Sea glass beach!!! MacKerricher State Park, CA, USA if this is a real place I want to go tomorrow!!