I was stationed at Dyess AFB in TX in 93. Worked with B-1's and C-130's. There was a B-1 that did a extremely low level flyby over Lake Breckenridge. Dont know how fast he was going, but it was awesome. So low he left a water roostertail coming off the back end of the aircraft.

The coolest thing Ive ever seen though was a F-18 super hornet, come streaking down the runway at Pensacola NAS, JUST under mach 1. He held it there as he did a low level flyby down the runway. I watched in amazement as he flew by with the sonic "wave" wrapped around the nose of the plane all the way down the runway. If he had gone a touch faster....BOOOOOOOM. He didnt break it, but he was RIGHT ON THE EDGE. It was cool as hell actually physically being able to see the sound barrier wrapped around the nose of the plane.

I think I might have some lousy pictures of it someplace, Ill try to find them.