I applied online and was contacted 1-2 weeks afterwards. After 2 phone interviews, I was invited to an on site at Sunnyvale CA at the beginning of March. The interview consisted of 4 technical interviews and 1 Engineering Director lunch interview. The overall technical interview process was well expected with the exception of one disagreement: One question was to determine the median of a stream of numbers at any given moment in time. I stated that, in the case of even amount of numbers, the median is the average of the middle pair of numbers after rearranged in ascending order. The Interviewer, at this moment, not only instantly denied this logic, but also got angry at me, stating that: "when there are even amount of numbers, the median can be either the lower or the higher element!". Although this was only a small disagreement, it made me feel like there is no room for discussions in the glorious halls of Yahoo!. Also, be very aware of the lunch with the engineering director. In the emails, it was stated that the lunch will be a strictly casual non-interview process. However, the Engineering Director asked me technical questions including algorithms and data structures and behavior and personality questions like: what do you want to do in 3 years, why do you want to join mail/antispam, do you like machine learning, tell me some machine learning techniques, where did you come from (which country) and at what age? So be prepared. Lastly and most importantly, it has been almost 3 months since the beginning of March, they still haven't given me the reimbursement for money spent on the interview. I was at Sunnyvale California for 3 days and spent roughly around 200-300$ for travel, food, and parking out of my own pocket. I have been emailing them every week regarding the reimbursement and all I get from the HR is that they will look up on it. It is almost three months now and all they can do is look up on it. I am only a student and it would be really nice to see that money again. T___T Be prepared to spend money out of your own pocket when you get called from Yahoo! for an interview.