We have developed a highly personalizable CRM that operates fully on WSS and leverages all the best of Sharepoint out of the box but is scalable and extendable to manage a growing business. This is an awesome platform for small companies that understand technology and wish to leverage third party products, be independent and not be constrained by the software they select. We were turned on to SharePoint 3 years ago. It is meeting the needs of organizations who don't want the SaaS route and nor do they want the out of the box license by user model. SharePoint provides such an excellent alternative but its still little known outside of document management and collaboration.