Agua fresca is a tradition in Mexico and Latin America and is served at a lot of taquerias, supermarkets, farmers market stands and parties in New Mexico. You can get it in a huge number of flavors--and colors!--from canteloupe to honeydew, cucumber-lime, strawberry, watermelon, jamaica (hibiscus), and the traditional horchata made from rice. If you go to a traditional Mexican market, sometimes the labels are in Spanish with no English subtitles.
According to Amy Scattergood of the Los Angeles Times, "in the pre-Colombian 15th century... Aztec farmers would paddle their canoes into Tenochtitlan (now Mexico City) with fresh fruit that they would mash and mix with water for a refreshing drink."
Below is a general recipe from Food Network for making agua fresca. You can also do a search on the internet and find recipes using a wide variety of fruits.
1 large cantaloupe or half a watermelon, seeded and diced (about 3 cups)
1 1/2 c. water
2-4 T. sugar
2 to 3 limes, juiced
This and other similar fruit drinks, which translate literally as "fresh water," are served all over Mexico and they're a cinch to replicate at home. The key is to strain the pulpy fruit to make a clearer liquid. Instead of melon, you could use strawberries, pineapple, or mango--any fruit that is soft enough to puree.
Puree cantaloupe and pour through a fine sieve to eliminate pulp. In a pitcher, mix strained fruit puree with water and season with sugar and lime juice, to taste.