Found this online:

Sports Tonic: The potassium and magnesium makes in a near perfect sports food for those lactic acid related cramps. I have personally found that a banana after a particularly grueling run or bike outing will relieve muscle cramps within fifteen minutes.

Other Uses: Once you've finished eating the banana don't throw the peel away; put it to good use. Because the banana peel is also loaded with potassium it can be used to reduce wrinkles around the eyes. Rubbing a fresh banana peel, yellow side out, under and around the eyes can reduce worry lines and bags. A banana peel can also reduce the itching and swelling from an insect bite. Again just rub the peel on the bite or for extended relief tape some peel to the bite.

Gardening: Rose bushes thrive on potassium so try scattering a few peels around the base of these bushes. In a pinch I even used a banana peel to shine my shoes.

So, a banana is not just good to eat, its peel is also good for your skin and good for certain plant

The banana peel trick works for almost, if not, all flowering/fruiting plants. I used to use them for my tomatos, hot pepper and my pot plants back when I used to grow. Epsom salts are also great as well for plants. I don't recommend it for indoor potted plats though because the peel will attract fruit and scuttle flies.

That's good to know. You should rep for Dole...

Try smoking one !