Please see http://blog.polychart.com/2013/04/licensing-model-of-polycha...

Polychart.js can now be licensed under a per-domain or per-company license. We continue to offer discounts to startups (as we're one ourself!)

Thanks for the comment and the feedback on the pricing. Please email team@polychart.com for a discount or alternative model just for HN readers, or if you have other feedback!