Nowhere in the Mindstorms NXT 2.0 instruction manual does it say that the screen of the control brick mustn't be hit by a two-year-old. With a pool ball. Not that it would have helped, as our two-year-old can't read!
The result is that we not have an almost brand-new lego mindstorms set which functions perfectly except that the screen is pretty much unusable. We'd like to know whether a replacement screen is available for the nxt brick. Watch these two videos of my ten-year-old controlling (and disassembling) the tank-style robot with a ball shooter and you'll see how cool it is.