bamboo is a new fiber on the market, along with "soy silk" (literally made from the left-overs of the tofu manufacturing process o.O I KID YOU NOT), tencil (which is made from cellulose from trees), ingeo (made in nebraska- from corn!!! haha), silk latte (made from- milk. yeah. I'm dying to get my hands on some of that stuff) and an increasing amount of others.
It's considered a man-made/plant fiber. The process of manufacturing it is somewhat complicated to explain. At anyrate its seriously cool stuff.
Soy silk has the edge over the others, IMO, because it's a protein fiber- the first (I believe) plant fiber that you can actually dye with the same dyes as you would for fibers from animals such as sheep, alpacas, goats, etc. Other plant fibers, such as cotton and linen, require a special kind of dye.
Which brings me to a surprising thing about me- I'm into "fiber arts", big time.

I've actually spun soy silk, haha. And I can take a newly shorn fleece, and do like the whole process from washing/carding/spinning/knitting into a garment.
In other words- if we ever get into WW3 and all our foreign trading is cut off, I can keep everyone in socks, lol.

---edit---
did you know that acrylic fiber is made from fossils?!?!?!
