Funny you should say that, Star...
My original idea had just that...good ol' batsy hangin' upside down outside the window with his face pressed against the window.
I was even gonna photoshop it to look like he was steamin' up the window with drool and stuff...
But my CS6 program corrupted, and I'm still waitin' for a fix file from them. Thus the No postwork on this image.
Perhaps I'll do a similar one when it's fixed to implement the idea.
Great minds think alike, huh?