GroupOffice is a groupware suite that takes your office online, implementing online collaboration and CRM. It allows you to share projects, calendars, files and email online with co-workers and clients. It is easy to use and fully customizable. It also features synchronization with PDAs and Outlook.
Exchanges is a Bash CGI script for collaborative creation of manuscripts. It allows new entries to be injected between existing entries. Owners of entries may edit or delete them. Anyone may comment on them. By default, one views the entire document. Exchanges are directory-based, with a single CGI handling multiple writing projects.