Well, a while ago, when I was a kind-of-cruddy docker, I was docking a Soyuz-like rocket to a station. I still had the orbital-insertion stage attached to it. I was like, "Ah, I'll just get rid of this thing." No pics, so I'll relive it in gory detail. I hit the spacebar. The second after I did that, I realized, "Oh, shoot, I'm still moving toward the station!" Looking at the Navball confirmed this: Dead on, at 10 m/s. And the stage was a dead stage, no probe, no RCS, careening at the central hub of the station. "Oh, god. Oh, god! NO!" ... It missed... by less than 10 meters. I was practically going to faint, as that station took a long time to construct.