Cronofy - Unified Calendar API for developers
Resource Central - Meeting room & resource scheduling software for Outlook
Campaign Calendar - Campaign Calendar by Bracket Labs builds a marketing calendar from your Salesforce Campaigns.
YArooms - YArooms is a web based booking software package that makes it easy for you to manage rooms and...
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.
Smartway2 - Book meeting rooms, desks & more via mobile/Outlook/desktop