From Hutchings Software:
Bosco's Screen Share is a new, easy way to share your computer’s desktop with your friends. Bosco’s Screen Share runs on Mac OS X, Mac OS Classic, and Windows, allowing you to share desktops regardless of platform choice. Bosco’s Screen Share uses a peer-to-peer, serverless protocol and leverages standards such as JPEG image compression and TCP/IP, ensuring excellent performance with minimal interruptions. Bosco's Screen Share also works with Personal Web Sharing so your friends can watch your screen in their web browsers.