Some typical areas of questioning I´ve encountered:
Describe xxxx system of the plane you have flown the most/least...
3 good/bad aspects of yourself
a problem you´ve encountered and how you solved it
if you mess up in a flight, what do you do? (dont know the right answer, but i´ve been told to not make stories up
)
my favourite: why did you start flying? duh!
what is your username in pprune (I´ve been asked that!)
why do aeroplanes have sweepback
what pilot maintenance can you perform in a charter IFR aircraft
what do you do if there is a bad knick in your 206´s prop out in the corner of nowhere?
be honest, and good luck