Mint is one of the herbs that has it all.  It grows like a weed, is perfectly safe for use, and is an excellent remedy for reducing symptoms related to digestion.  And it tastes good going down!  They don't serve after-dinner mints virtually everywhere you go for nothing.  It is well known for its properties related to indigestion, stomach cramps, menstrual cramps, flatulence, upset stomach, nausea, vomiting, and colic in children.  Make a Tea out of fresh or dried leaves for a tasty and refreshing after-dinner stomach soother.  For the younger crowd, it can also be heated with milk for the same effect (and they will like it).  

Mint also can be used as an appetite stimulant.  It reduces hunger for a short time, but when the effects wear off the hunger returns stronger than before. For those lucky enough to need to gain a few pounds, a tea might be tried 30 minutes before a meal for appetite stimulation. 

Peppermint is much more effective as a medicinal herb than Spearmint, which is mostly a culinary herb.  However, use Spearmint in place of Peppermint in cases of digestive problems or colic in very small children, as Peppermint may be a bit too strong. 

For a refreshing and cleansing facial wash, place a handful of bruised Mint leaves (any kind) in a quart-sized pan of cool water. Let sit for an hour or so, then chill in the refrigerator and use as desired.  Mint combined with Rosemary in a vinegar is reported to help control dandruff  (place the sprigs in a bottle that can be tightly sealed, and let sit for at least a week out of direct sunlight). 

New research indicates that mint oil used externally in a cold compress or rubbed directly into the skin can significantly reduce pain in cases of arthritis and chronic joint pain, with few if any side effects.  See how to make herbal oils and ointments for information. 

Lastly, any of the mints make a good addition as far as taste when making herbal teas, and as such, having a few mint plants growing in the garden is a must for anyone serious about herbs and their medicinal uses, as a many of the other herbs have objectionable tastes that can be masked by the addition of one of the mints.