AMAZONIA10
I received an email from GoodnessMe when my subscription ended, offering me $10 off if I resubscribe with code AMAZONIA10. I tried this code without logging in though and it still works. They usually have a freebie of some sort for subscribing, but in the 6 months I've been getting it, I haven't seen a discount code before.
They send a box with natural/organic food; it's pretty ace. I've tried quite a few different box subscriptions (Native Box, and another, whose name escapes me) and these guys are the best by far.
It's valid on all new 3, 6 or 12 month subscriptions. I suggest getting 3 months, as there will probably be another cool freebie when your subscription finishes :)