We have a major ladybug invasion every year around October. Not so bad this year, I think they drowned in the rain. But this was the worst year, 2009:

They get inside through cracks and there's piles of them in the corners of the ceiling. These are the Asian ones and they bite. If you disturb one, they stink. Smush one, they stain.

I like ladybugs, but not these...