As part of Office 2010 extensibility, it is now possible to extend Context Menus exists, e.g. adding new buttons to a particular context menu in Word/Excel/etc.. To extend a particular Context Menu developers need to know the id name of that particular Context Menu; for that purpose UEX publishes every release a list with all the names of all the extensible controls in Office. However, is not easy for developers to look at the huge list and find the context menu he/she wants to extend because sometimes the names are not meaningful. To help developers with this task, Julián Argil Torres has developed a small add-in that adds at the end of the context menus a button with its name, also if the developer clicks the button, the name is stored in the clipboard.

You can find a link to the add-in at http://msdn.microsoft.com/en-us/office/aa905530.aspx