yea have that book and I know its common for Cider, I was watching the Oz and Hugh beer program the other day ( again) and some chap used kidneys, Oysters and Jelly fish.
I have been thinking that as I eat a great deal of Monkey Nuts I could put the shells in the mash as they may add something if not help the mash bed( but never had a problem with stuck mash, but now I will

).
Still might try a SPUD Beer or Beetroot but not until I brew up another CITRA-SMIFF as thats a good beer but my automatic beer saver has kicked in and I can't sample any more at the moment

( the Gas has run out and need another bottle)