Met staff during a college career fair. We talked about me, who FactSet was (I had never heard of them), and we talked about how it might play to my interests. I gave them my resume after talking.
Several days later I received an email asking for me to set up a phone interview, which followed a couple days later. The interview was a few simple questions, procedural programming stuff, with no OOP or anything. I got an email later that day to set up an on site interview.
The next week I went in for an interview that lasted approx. 7 hours. It consisted of 5(6?) 2:1 interviews about things like debugging, OOP, design philosophy, etc. Talked about my resume with every group, and got to know each of them. On of the groups took me out to (a nice) lunch and we talked about my interests outside of work. The final interview was with the lead boss, which was about 1/2 an hour, and I was given some tougher problems to solve conceptually.
3 days later, I got an offer.