Screenleap,

Screenleap is a Y Combinator-backed company that allows you to share your screen and view it from any web-enabled device without installing any software. Our mission is to do for screen sharing what Dropbox did for file sharing: make screen sharing a hassle-free experience that just works across all devices. We also allow developers to add screen sharing to their applications using our API (http://www.screenleap.com/api). Our screen sharing service has been integrated into a variety of products and services ranging from audio-conferences services to e-learning platforms, sales tools, and support applications.