I can't figure out how to do the Amazon link properly but here's a link to the reddit thread where I found it.
http://www.amazon.com/dp/B00VH1J4SU/?tag=cl03f-20Use promo codes: LGG4REVW & VERUSRVW
A couple of things:
It only works on the green one, although some people in the thread say it worked for them on the others.
In the buying options, choose the one with out free shipping.
The first code brought it down to 17 cents for me, the second made it completely free.