Strad
Sorry Tanker but to answer your question, basically bu--er all. Yes some buildings are used to house unmentionables but others such as the hangers went years ago. If you have a squint on google earth you'll see that virtually all of the airfield has gone, most of its concrete used as hardcore for the new M11, well newish. There is a memorial on the site which is well looked after. Also, if you are interested there is a book on the history of RAF Stradishall written by a chap I used to know called Jock Whitehouse and his mate Spencer Adams. A good very well researched read!