Last week, it was the monthly meeting of the Huddersfield branch of the Knitting & Crochet Guild, and we had a workshop run by a local member, Elizabeth Smith. Some of her knitting and crochet is based on what you find on beaches - seaweed, pebbles, sea anemones,... You can see one of her seaweed covered rocks here, along with one of her beautiful cushions in stranded knitting, based on local Yorkshire landscapes. We didn't attempt anything very ambitious at the workshop - we just knitted strands of seaweed. I have knitted quite a bit more of mine since the workshop.
The yarn is Jamieson's Spindrift, in the Granny Smith colour. I've also experimented with another variety of seaweed, in Moss, with more complicated branching (but have run out of yarn.) It's very satisfying to see how it develops, and I know from seeing Elizabeth wearing some of her knitted seaweed that it looks good worn as neckwear - she says it's surprisingly warm too. The plan is to combine three strands in different greens, and wear them together.