Amazon Lab126 contacted me for an interview after I gave them my resume at my campus career fair and attended an info session for them. They came to my town and set up a day of interviews for all the candidates at my college, and allowed us to pick a time during the day from several time slots. There were two 45 minute in person interviews that were behavioral and technical. Both interviewers asked me about past experience from my resume, and went into detail about the internships and projects I had done. There were a few very basic technical questions (ie low pass filters). The environment was overall relaxed and I felt very comfortable speaking with both interviewers, they were nice people and very welcoming to questions at the end of the interview. They told me they would let me know in a month, and were accommodating to letting you know sooner if you had other offers with deadlines. I got a phone call with the offer a month later.