Nature is full of interesting goodies. My favorite is the discovery taq polymerase from thermophile bacteria that lives on thermal vents at the bottom of the ocean.

http://en.m.wikipedia.org/wiki/Polymerase_chain_reaction

Another form of code reuse!

I also wonder what amazing things we could find in rare/niche ecosystems giving that in such a short time we've seen things like this and rapamycin.