Add the corn to a large pot and cover with water. Bring to a boil over high heat and continue to boil for 10 minutes or until corn is soft when poked with a fork. Drain and set aside to cool. 

Halve, core, and seed the jalapeno. (Leave the ribs and seeds if you prefer more heat.) Halve, peel, and dice the onion. Halve the cherry tomatoes and cut the cucumber into 1/2 inch cubes. 

Mince the mint and cilantro until you have about 1/4 cup of each. 

When the corn has cooled, cut the kernels from the cob. In a large bowl, combine corn, onion, jalapeno, cucumber, tomatoes, cilantro and mint. Stir to combine. Add the olive oil and white wine vinegar and stir until evenly coated. Season generously with salt and pepper. Add the feta cheese just before serving.