Trek is both a Web browser and a new kind of social network. It allows its users to meet and interact by overlaying the Web with graphical avatars. Said avatars represent each user on a given page and can be moved freely about the content. Users can form parties or "browsing treks" and move about the Web in a group.
Event is a simple PHP-based software package for creating a simple Web page for upcoming events. Event supports an unlimited number of events, each with its own mini-site, each of which is configured by a single text file. Event is designed to run in constrained environments, and without needing write permissions from the Web user or database access. Event supports localization into additional languages.
robonobo is social music sharing and downloading software. It allows you to share your friends' music libraries and playlists, stream the audio instantly, and download the file in the background so you can burn it, export it to your music player, or do whatever you want with it. You can import your friends list and share links to your playlists via Facebook and Twitter.