Mycobond  

Transmaterial has a post on a new use for mycellium as a bonding agent - Mycobond.

Mycobond is a mycological bio-composite that can be used in a wide variety of applications. Instead of conventional manufacturing processes, Mycobond uses mycelium—which is essentially the root system of a mushroom—to transform loose aggregates into strong composites. This process can be varied by using different species of fungus and mixtures of aggregates in order to make a composite with an optimal density, strength, appearance, and performance for the specific application.

Additionally, Mycobond represents a low-embodied-energy manufacturing process as the material self assembles at room temperature and pressure in the dark. Furthermore, Mycobond upcycles resources like rice hulls, cotton burrs, and buckwheat hulls that are otherwise thrown away, transforming them into valuable products, including rigid board insulation and protective packaging buffers.