I was out running errands over the weekend and was passing through Pottery Barn - and discovered that they have some fabulous beach towels. And they're all on sale right now. ($39 regular price, on sale now for $29 each). They're generously sized at 40 x 72 inches and are finished with a fast dry finish so they'll dry faster.
These 2 floral designs are my favorite.
I also like the realism of the ocean inspired designs.
Seashell Beach Towel