Cronofy - Unified Calendar API for developers
Planmesh - The easiest way to plan with friends
Campaign Calendar - Campaign Calendar by Bracket Labs builds a marketing calendar from your Salesforce Campaigns.
Travel Diaries - Create your own travel diary to capture your experiences
ApPHP Calendar - ApPHP Calendar is a PHP calendar script that may be easily integrated and used with various PHP projects, such as schedulers, event, etc.
RoomForTea - A female-friendly housing network in London, UK.