The first one http://elderberryink.livejournal.com/264.html is sheer delight for anyone who has enjoyed the series "Black Books."
The second one is http://community.livejournal.com/crossover_hp/66443.html
IMO, Dr Who is one of those special characters who can work with ANY fandom (if written well!), and this one was well done! The author captured Nine beautifully and tied the universes together cleverly.