I applied through university. The process took 2 weeks. I interviewed at Group One Trading in Oct 2013
Interview
Interviewed through a campus visit.
Had additional phone interview as well. The interview process was very direct and didn't not hide the amount of coffee runs and food runs an intern would be making. It was mostly case based and the interviewer was most interested in the resume. There were a good deal of probability questions and questions about the difficulty of your class load.
Interview questions [1]
Question 1
Would you rather have a lottery ticket with a 1/100 chance of winning a million dollars or 100 lottery tickets with a 1/100 chance of winning 10,000 dollars?