From Zoya's blog:
"
Zoya Nail Polish Exchange*
Keep the planet a little bit greener one bottle of nail polish at a time!
Announcing the 2010 Zoya Nail Polish Exchange. For a limited time, kicking off on Earth Day (April 22, 2010 - 12 PM EST), Zoya Nail Polish will exchange your old, out-of-style, unwanted nail color and replenish your nail polish supply with fresh Zoya fashion colors. Simply send in six or more bottles of old polish - any brand other than Zoya, Qtica or Nocti, new or used - and we'll send you the new Zoya colors of your choice in a bottle-for-bottle exchange.
That's right - no exceptions, no questions. All you pay is $3.50 per bottle to cover shipping and processing. Choose from over 300 formaldehyde, toluene, camphor and dibutyl phthalate (DBP) free, long-lasting, award winning, healthy colors to replace your old color! Zoya will properly dispose of your old polish according to EPA guidelines.
* Any brand other than Zoya, Qtica or Nocti. New or used, empty or full. Minimum of six bottles. Send with the required shipping, processing fees and documentation to have the old color disposed of according to EPA guidelines and to qualify for NEW Zoya Nail Polish at no charge. Shipping and processing fees required for exchange. Restrictions apply. Available in continental US only. Limited time offer. Exchange ends June 30th, 2010."
Technically, this isn't free since you'll have to pay $3.50 per bottle as well as any shipping fees to send your bottles to Zoya, but still, it's like getting Zoya for half price and thankfully it's for a decent amount of time so no need to furiously sort through polishes you may dislike or anything. Will you be participating in the exchange?