the thing serj is sucking on is called a camal pak and like holds water or something and u just suck on the tube and the liquid comes from the pack.... YUMMIE!
i think its like a key baord from an accordian...you know but he took it apart so he needs to blow thruogh that tube thingy to make the key baord part work
its actually called a pea-monica... you blow in it.. it sounds like a harmonica, and you use the little keyboard. one of the local bands i saw round my place used one...