I had an ongoing war with the pigeons on my fire escape (just outside my bedroom) for about two years. And then I solved it.
First off, I don't care that they were there. What I cared about was the incessant cooing -- and then the screaming of the baby birds once they hatched. It always sounded like children screaming to me, which was disturbing. And the cooing began waking me up in the morning.
So I bought a super soaker. But they're not idiots -- the pigeons learned to fly away when I opened my window and always came back later -- and I accidentally even sprayed someone passing by on the sidewalk once, so after going though two of them I decided to think of something else.
I went out and tossed away two non-egged nests. They still came back and built more, faster.
And then I remembered something my mom did. She hates birds of all kinds and didn't want even sparrows making a nest in the bird house she hung outside (as decoration only!) So she hung up a sock with mothballs in it, and that worked. Why it took me so long to think of this myself I have no idea. But I went out with two socks filled with stinky mothballs, tied them together looped under one of the grates on the fire escape, and have not had a pigeon problem since.
They have moved one fire escape down, but I can't hear them now at least.
So there you go: Mothballs + socks = no pigeons.