It would be a little bit like Christmas when you still believe in Santa, when you open the present and you go "How did he know I wanted this?! Ahh, it's perfect!!" and it's unexpected and, well, magical to say the least.
I also expect the look on my face to be vaguely the same, except with a touch of pink blush on my ears from nervousness (Or would it be embarrassment that I wasn't presentable?).
...I'm happy :)