Google Noticeboard is an application that helps people access and share information over the Internet using public digital noticeboards. Using Google Noticeboard, communities can access a variety of relevant information. People can create text messages or record voice snippets and post them to one or more noticeboards. Typically each digital noticeboard carries publicly accessible messages. Compared to the notion of personal communication using email accounts, the Noticeboard metaphor allows user to engage in public communication with communities.
Communities with access to shared computers can use the Noticeboard for exchanging messages related to community announcements, social interactions, local buying and selling, and information that is of wider interest to the community. The Noticeboard may also be used for the community to engage in a dialog with benefactors, public servants, and other service providers who are geographically distant. For example, residents of an apartment complex can use the Noticeboard for posting announcements, or NGOs who own and operate computer centers in several villages can use the Noticeboard to enable village residents to communicate amongst themselves
Noticeboard uses a Firefox extension and requires to enable IMAP in Gmail to send messages. The service seems to be aimed at people that don't own computer and don't have an email address, but the interface is very basic and limiting. Google Noticeboard's user guide (PDF) has more information.