It sure did happen - September last year. Blair flew in from Washington on a BA 777 on his way to brief the Queen about the Iraq situation whilst she was staying at Balmoral. Presumably a fairly empty plane with little fuel left at that point.
No photos of the 777, but here's a link to a couple of photos of an A330-300 landing at ABZ last year - and that one was full of 300+ German football fans so wasn't too lightweight!
http://www.airliners.net/open.file/275168/L/
http://www.airliners.net/open.file/275169/L/