The first example I have seen of Microsoft Web Clipboard, uses Microformats – hCard and hCal. The demo lets you copy paste a contact or an event on a web page. Currently this demo works in a single page. To my pleasant surprise, it works well in Firefox 1.5.
There is code and links to the necessary files in this page for you to build your own application. The Live Clipboard XML data format is the core technology for building these applications. This still seems to be evolving. According to this technical summary:
A preliminary specification for the Live Clipboard XML data format is in the works. Please keep in mind that the data format used by the control in the example will change somewhat by the time we release the specification. When this happens, we will update the control here, so if you are already using it on your page you will have to update it with the new version. Also, if you write code that uses the WebClipData object, you might have to modify it slightly.