Jolicloud, a custom-made Linux OS designed specifically for netbooks, has an emphasis on bridging the gap between web and desktop applications. It also heavily focuses on social activities and has the capability of sharing your computing activities (such as when you install an application) with your Jolicloud contacts.
The Jolicloud netbook OS is still in alpha testing, but recently, all existing Jolicloud users have been allowed 10 invites, which they can send out to their friends. If you’re interested in checking out the OS, start asking around. Maybe your friends can send you an invite.