Potassium Permanganate can be used for:
Water purification (slightest visible purple tin coloration in water is enough)
Desinfecting wounds and fungal infections (add crytals until you have pink colored water)
Yes, fingernail fungus as well ... http://www.tipking.co.uk/tip/5988.html
Singals in snow or clear water (making a purple solution and spreading
it in a distress signal patter such as an X or SOS.
4 Lbs Potassium Permanganate
WARNING:Potassium Permanganate can be very dangerous and fatal, avoid
direct contact with skin. It is deadly if you eat the crysals directly
or drink large quantities. KEEP AWAY FROM CHILDREN!!!!