Not even just smaller companies if you know someone high enough up :-) Every job I've had since right out of grad school has basically come through sending someone I knew an email.
That's really the answer although it's probably not very actionable for a lot of more junior people.
I know you'll find people who say they've always just gone through recruiters or applying online, but beyond starting out it certainly hasn't been my experience--including in difficult periods like 2001. I'm sure I've been lucky but it's also resulted in the right jobs through the right people.
That's really the answer although it's probably not very actionable for a lot of more junior people.