We have one of these on display here in the National Museum of the US Air Force in Dayton, Ohio.  However, I do not believe that it's operational.  Tom, if you ever make your way to Ohio, make sure you stop by this place. This museum, is the largest military aircraft museum in the world. It has more aircraft than the Smithsonian.,(reply>), @Andrew Ireton that plane is a huge draw for people. If I remember right I believe it's in the Cold war section. You can take a virtual tour of the museum on their website.,(reply>), I'd like to see the XB70 there one day.