Eleven popping out of the cake at Rory's stag do was great as well.
DOCTOR: Rory! That's a relief. I thought I'd burst out of the wrong cake, again. That reminds me, there's a girl standing outside in a bikini. Could someone let her in and give her a jumper? Lucy? Lovely girl. Diabetic. Now then, Rory. We need to talk about your fiancée. She tried to kiss me. Tell you what, though. You're a lucky man. She's a great kisser.
(Someone drops his beer glass and it smashes on the floor.)
DOCTOR: Funny how you can say something in your head and it sounds fine.