"It's a peer-to-peer app. But not the kind you're thinking of. Grouper isn't like Kazaa or Morpheus, a way of sharing files (often illegal versions of copyrighted material) with millions of strangers across the Internet. It's a way of sharing private files with people you know—your friends, family, and colleagues. Rather than tapping into one, enormous, worldwide peer-to-peer network, it sets up small, private P2P networks, including only the people you tell it to include. With no more than a few clicks of the mouse, you and up to 29 buddies can instantly share most any file from machine to machine, including photos, videos, songs, and documents. And it won't cost you a penny." Seems like a nice easy way to share video, photos and other files with friends and family. The only drawback I see is you have to use their software. For this to truly be usefull, the client should be available in a browser (active x or java) so that end users don't have to figure out how to configure the P2P client.