The Boeing T-38 chase jets are something I have not had much success in hunting down.  I have got some shots but they were not in great conditions.  I did have another chance recently when at Boeing Field but, guess what, the clouds rolled in at just the wrong time.  The T-38 flew nicely down the approach and provided a great opportunity but the light was not really playing ball.  Still, at least I got some shots, even if the colors are hardly popping.