SpiderOak is a cloud-based backup and restore solution to protect against data loss.

Linphone is a free voice over IP (VoIP) service and SIP client.

Jitsi (formerly SIP Communicator) is a free and open source multiplatform voice (VoIP), videoconferencing and instant messaging application.

Wiki on a Stick is a wiki that lives in one self-modifying XHTML file.