Nocturnal is an automated Messenger-based information sharing and collaboration web-search system.

Nocturnal provides automated information sharing between Messenger users. A browser enhanced with our personalized collaborative-search tool bar uses URL recommendations that are shared through Nocturnal and stored to a local database in order to filter MSN-search results and bring URLs recommended by peers to higher importance.

The vision behind the Nocturnal project is to harness the power of social links for sharing information such as recommendations and reviews. The key idea is to leverage the existing messaging network in order to bootstrap the system with natural, automatic social communities. The communities are formed by a user’s buddies list, his buddies’ buddies and their buddies, and so on. Each social circle shares much in common, without requiring users to subscribe to any new service, eliciting information about users’ hobbies and social behavior, etc.

Nocturnal automates information exchange within these social circles using the existing messaging channels. It uses the Messenger Folder-Sharing feature to facilitate exchanges between a user and her Messenger contacts. A user Alice exchanges data with her immediate contacts, and stores the information she pulls from them on the local disk. Alice’s contacts exchange information with their contacts, and in this way, information from Alice propagates to her contacts’ contacts, and so on, until any hop-limit she sets. The information arriving at any user is stored in a local database, along with tags indicating the distance it came from and the path. In this way, Nocturnal builds a social  information-sharing infrastructure in a peer-to-peer manner.

In order to address trust concerns, recommendations shared in Nocturnal include an origin and the number of hops they transfer through. A Nocturnal user controls how far in the network to pull information from, or how far to send it, usually bounding it to several hops away.

Nocturnal is used for sharing URL recommendations among Messenger peers and forms a personalized, collaborative web-search tool. Collecting URL recommendations is done in either automated mode or manual (or both): For the former, the user may allow automated copying of  her `favorites’ files. For the latter, she may voluntarily click a `recommend’ button on her browser.

Nocturnal is divided in two parts, one is the shared folder in Windows Live Messenger, the second is part of the Windows Live Toolbar