I kind of posted this topic once before - about what player aids you use to help keep you and your players thinking like 10 year olds. With renewed action on this board I would like to expand that a bit and ask What player aids do you use, period? Any pictures, music, items, etc? In other words, anything besides the book, paper, pencils and dice?
I for one give my players homework. It is dreaded but well received. If they do the homework i give them a 5-6 Boost for the following session. Examples have been - Come up with an example from TV or cinema of a character that fits your own Grimm character's archetype, bring a snack food to the next game that was your favorite when you were 10 years old, and (when the were going to the Land of Fear) decide what your character's greatest fear is.
I frequently look for pictures on the Net that I can show on the big screen when the players encounter them - different castles that they encounter, pictures of creatures/monsters they encounter (like bridge trolls, for instance) or spooky shots of creepy forests. This is how i ran across the fabulous pictures of Gary Busey as the GingerDead Man.
I made a storyteller screen with pictures from the Grimm book facing the players. I also have a horror theme track playing in the background as we play (Midnight Syndicate)
I would love to hear anything that the rest of you do.