A really useful map of the frequency range of different instruments, good to have when you are mixing. When you hover the mouse over different parts of the map it displays additional information about the instruments such as its generated frequencies and the ears ability to pick them up.
You notice pretty much right away that an electric guitar really doesn’t stand a chance again counter bassoons and church organs :-D
http://www.independentrecording.net/irn/resources/freqchart/main_display.htm
Static screenshot:
