We had two boys that were VERY into superheroes, and were lucky enough to have a friend with a Batman costume.
What People Ate
cake, cupcakes and ice cream
What People Drank
the Birthday Boys faces when Batman walked onto the porch
watching people pose in front of the backdrop with the 'BAM!' and 'POW!' signs
Batman, of course!
superhero candy and stickers
Activities / Games
building and punching through a "brick wall" made of boxes, using "spider spray" (silly string) on the bad guys, and trying on capes in the phone booth
I pick up things year round, so I probably spent around $100 total