Zarta, a new ad-free creator platform that focuses on pay-per-view video content, announced today that it has closed a $5.7 million seed round led by Andreessen Horowitz (a16z). The platform allows creators to upload videos, set parameters for a free preview and then charge viewers a small amount to unlock the whole video. Zarta is currently in limited alpha testing with a small set of creators, with plans for a broader launch later this year.