In the Gnomemurdered book, I focused a great deal on Gnomish mutations (from contact with Gnome goo), and I went into some detail about Gnomish cookies and the dangerous side-effects they provided.
Are there any other well-known byproducts of Gnomes, or popular products associated with Gnomes, that could be material for unusual effects in a Gnomemurdered game?
RPGPundit