Ask HN: Best ways to drown out invasive thoughts and focus on a task?

There are many times for me when silence is more deafening than a loudspeaker. Okay fine that's hyperbole (mostly), but I often do like to have white noise of some kind (music, etc) in the background when I'm programming, planning, thinking, etc. It helps to restrain the random thoughts that fly through my head that take my focus away from what I'm doing. So my question is in what way(s) do you accomplish the "simple" task of focusing on one path when your mind seems to want to go in a thousand different directions?