Important: This whitepaper applies to Internet Explorer 8 Beta 1, and has been removed. For current documentation, please visit the corresponding page in the Internet Explorer SDK:
Per-Site ActiveX Controls Internet Explorer 8 Beta 1 for Developers allows for greater control of where and under what context ActiveX controls can run. In this version of Internet Explorer, ActiveX controls that are embedded as Web objects are presented to user as add-ons. Through the Manage Add-ons dialog, the registry, or ATL SiteLock, these add-ons can be restricted for use on specific Web sites.
[Update: 3 April 2008] Updated link to SiteLock template (v1.14).