Had an interview start at 9am and end at 2pm. Although there was a few of us in the room, we were doing tests all day. Seemed to last for ages.
Funniest one was when I went for an IT job and they left me in the room for 45 minutes when they said they would be a few minutes.
Got a bit bored and started drumming on the desk and looking out of random windows at cars.
Then to be polite, when they walked in and apologised for being a 'little' late I said 'Oh, it's fine' when in actual fact I was so hungry my belly started growling through hunger and continued for the rest of the interview.
Oh btw - congrats!