The Lyon Air Museum has a B-17 as part of its collection.  Named Fuddy Duddy, I was told by a docent that it is airworthy.  I don’t know whether that means it is still flown or not and a quick search has not brought up any recent photos of it but maybe it is out and about at times.  I walked around it in the hangar and got a few shots of it in amongst the rest of the museum collection.  It looked to be in great condition but I have no idea what is beneath the skin.