Workaround for missing "Edit WCF Configuration" menu option in Visual Studio
Sometimes when you have a clean install of Visual Studio 2005 or 2008 the context menu item "Edit WCF Configuration" for a app.config or web.config will not show.

The picture above does show the menu item I'm talking about, but you may find that it is not there.
Help is at hand: there is an easy workaround. Simply open up the Tools menu in Visual Studio and choose "Wcf Service Configuration Editor". This will start the exact same tool, but doesn't open your web/app.config. Close the tool straight away and right-click you config file. The "Edit WCF Configuration" context menu should be there now.
I don't know exactly when the context menu goes missing, but I found that it occurs regularly for Virtual PC images. It might be totally unrelated to that though. The workaround works in all cases I encountered so far.