IE4RC means Internet Explorer toolbar for RemoteCalendars. It's a COM-.NET plugin for Internet Explorer, which it'll make it possible to subscribe an iCalendar (RFC 2445) in Outlook if RemoteCalendars is installed. It'll add also support for webcal.

I'm proud to say that the first version of IE4RC is finally available! Installing this extension for Internet Explorer will give you something quite similar to the usability of iCal under Macintosh.
How does it work? Just remember to close any instance of IE you've got running, install and you're done. Then, when'll you right-click on a link on Internet Explorer, you'll be able to choose "Subscribe to RemoteCalendars". Click it and Outlook will start (if it wasn't running) and you'll have already set the subscribe form!

Project site page:
RemoteCalendars page:
Direct Download of RemoteCalendars:
Direct Download of IE4RC: