CRM Extras is a project to collect common shared extensions to Microsoft CRM.
It starts off with CRM Sync, which allows a Microsoft CRM database to be synchronized with a disconnected webserver. Use it to link your website sign-up system so that it automatically creates a Contact in CRM. Use it to publish your CRM Knowledge Base on your website.
Future developments will extend this to include usage of this data, for example the ASP.NET Controls that can publish the Knowledge Base, or the ASP.NET MembershipProvider that uses the CRM Contact table