Open source alternatives to Microsoft Products

Here is a list – based on my own compilation and personal xp (experience). Does not mean a feature comparison, which is better which is not and definitely not, Open Source vs Microsoft. Just a list, a mere informative list, to start looking:

• Microsoft Biztalk: Jitterbit
• Microsoft Commerce Server: osCommerce
• Microsoft Dynamics CRM: SugarCRM
• Microsoft Exchange Server: Zimbra
• Microsoft Office SharePoint Server: Alfresco