FreeMiCal allows the bulk export of MS Outlook appointment items to RFC 2445 conformant iCal format. .NET 2.0 or greater and Outlook 2003 or 2007 Interop Services required.
CentraView - Browser based Enterprise Java (J2EE) Contact Management, Groupware, Collaboration, CRM, SFA, Project Management software. Run locally or as a hosted service. Built on Apache Tomcat, JBoss, MySQL, Linux (Fedora, RedHat and others) & Windows
Leavecal is a vb.net application that helps your company keep track of annual leave days, public holidays, maternity, sick days and more. It is a leave calendar based on South African rules but it allows you to customize it for your business or needs