The only time I did an intray exercise was in questionnaire form which asked me how I tackle various admin jobs. It gave different scenarios like the phone is ringing, you have 20 urgent emails which need answering before the end of the day and then someone turns up unexpectedly demanding an urgent appointment - how would you make sure you deal with all of these things. These answers had to be written down . Think I was given about 30 mins to do it. I was offered the job but didn't end up taking it as I was offered a better one.