GroupWare   
http://www.altn.com

MDaemon GroupWare unlocks the collaborative functions of Microsoft Outlook using MDaemon as the mail server platform. Outlook users can share Calendar, Tasks, Contacts, Notes, and Journal folders without the expense or expertise required by Microsoft Exchange Server. Features include user configurable permissions where GroupWare users has control over the permissions of which folder(s) they wish to share with other users, WorldClient (MDaemon's web-based email client) will allow you to see items in your Outlook calendar from anywhere, and GroupWare licensing is independent of your MDaemon license size.

4Team for Outlook   
http://www.4team.biz

Manage your teams and projects in Microsoft Outlook with this easy-to-use workgroup utility without or with a server. Using an Internet connection (dial-up or broadband) or your company's intranet, your team members can create and share their multiple projects' workspaces including a calendar, contacts, documents, tasks, and discussion boards. Define member's access rights, post news, assign tasks, find members' free/busy times and organize meetings, discussions, and teamwork on shared documents, and control and centralize members' activities. You can use this product as an ideal instrument for remote companies and groups or just for sharing Outlook data for personal use. Now all relevant information and documentation can be placed in one location, only accessible by those with permission. Whether there are Web pages, spreadsheets, word processing documents, or any formatted material, it is available round the clock for those who need it. Let team members know their role, their tasks and their schedule. With a team task list, team members have instant access to their contribution to the project. Create a contact lists. Have a single place for team members to access the list of contacts important to your project. As the project develops, the list can be easily updated, so that everyone on the team has the names and contact information of those involved. Administrating does not require any special skills. You team can synchronize data among Outlook 2000/2002/2003 users, running in Windows 98/Me/NT/2000/XP, and supports Exchange and non-Exchange Profiles. You can also access Outlook data over Internet using 4Team Online Service. The version for Outlook 2000 is available from product website.

MyLook   
http://www.scibit.com

MyLook is a commercial personal/groupware information management (PIM) product developed by SciBit, using an open database structure standard, to be used in a workgroup environment, much like you would use Outlook® & Exchange® for collaboration. MyLook uses MySQL® Server as message store and provides mail(email), contact, calendar, task, note, link(url), app(shortcut) and group folder types. All these folders may be shared by a workgroup utilizing all the latest technologies. Mail, Contact and Calendar information may be exported in industry standard formats and importing tools for Outlook® / Express® / Netscape® / Mozilla® / Eudora® / Pegasus® are available or currently being developed.

Schedules4Team   
http://www.4team.biz

Schedules4Team is an ideal workgroup collaboration tool allowing you to create and access a common workgroup Microsoft Outlook calendar, Free/Busy time and share appointments, meetings, events and resources without a server.Create multiple groups, set individual access rules and manage projects between different workgroups or companies. Work online or offline and automatically synchronize data with your teammates. Print Schedules. Support of Microsoft Exchange profile.

ShareCalendar   
http://www.4team.biz

Share Microsoft Outlook Calendar Folders without any server. Share different Calendar folders with different group of people. Create Group Calendar. "Subscribe" your folders' / subfolders data for your clients. Share Microsoft Outlook Calendars with your own custom forms and imported items. Work offline or online. Labels (colors) sharing in appointments sharing. You can synchronize shared Outlook items with your PDA or Palm device. Synchronize Outlook Calendar data between your desktop PC and laptop. Simple access control. Easy-to-use workgroup application. Start sharing in minutes.