I applied online. The process took 1 week. I interviewed at 3M (Saint Paul, MN) in Feb 2012
Interview
I applied for the Summer Intern position in 3M this past Spring. I am mainly interested in Computer Vision and Machine Learning. They have a lab which works in this area. I was called for a phone interview.
Interview questions [1]
Question 1
The interview was very informal. There were two people interviewing. They asked just about what was there in the resume. The interview lasted for about 25minutes. They said I can expect a reply in the week after the interview. Never heard from them again.
I applied through an employee referral. I interviewed at 3M
Interview
It went smoothly. I was asked about my interests and future plans. I was also asked about my favorite subject and why I liked that subject. It was one-on-one and for 30 minutes.
Got the interview though on campus recruiting. One 30 min interview after an initial recruiter conversation that lasted around 5 mins. Took about 5 or 6 weeks to hear back from the company. Very typical process.