I have just posted an updated/expanded version of my
Rippert & Saint-Exupéry article on my website, with a commentary on an interview and an article that Lino von Gartzen has done for German newspapers.
This also includes additional links, to Jan Bobek's piece amongst others (thanks again, Jan).
Franek & Fairlop: I can do a guide to ULTRA, in fact I'm fairly sure I've done it before (maybe it was on the Luftwaffe Archives Group forum? Richard Eger could remind me). How quickly I do it depends on whether I have to start all over again or I can find the previous version. There is one condition: you must promise not to use any of the files I want on the same day I want them!