Interviewed via a recruiter, one 1 1/2 hour phone screen, a week later, a 10 hour at home coding challenge (they pay you for it), a week later had a 6 hour in-person interview (with an hour lunch in the middle).
This is by far the most grueling interview I have ever had. Every horror story you hear about interviews was present in this one, I was brain dead by the end of it.
But it was a good thing to see that they have such high standards for who they hire - all the easy interviews I've had in the past had code-quality equal to the difficulty of the interview.