I guess I'm a crammer. Short term memory is an amazing thing. I don't stay up all night but I do try to study as much as I can, just before the ride, on the complicated things had the toughest time with.
Something like light gun signals. I couldn't remember that one for more than a day, but if I read through it just before the ride, I could probably spit it out to the examiner.
I'd highly recommend the Oral exam guides by ASA. Also, as somebody mentioned, getting a breifing on things the examiner likes to do could be a big help. Lot's of good advice at the threads above.