The document summarizes three different ways Microsoft deploys SharePoint on the internet or extranet: 1) Spsites.microsoft.com which hosts thousands of WSS sites and my sites, 2) ICE which provides a hosted SharePoint environment through topics and areas on myice.partners.extranet.microsoft.com, and 3) An IT WSS extranet deployment which uses existing AD accounts for partner collaboration through a standalone deployment in the DMZ secured by two-factor authentication and other measures. The document also discusses security, cross-forest, account management and client-facing challenges faced by these types of extranet deployments.