When I used to work in the kitchen one of my co-workers taught me this summertime favorite. It also requires zero cooking if you happen to have leftover grilled corn on the cob.
1/2 c. Bulgarian feta, cut into small chunks (Bulgarian feta is much less salty than Greek. The guy I worked with also had a long story about how the Greeks stole feta. I told a Greek friend that one time and she got a little defensive.)
1/2 c. chopped tomatoes
1/2 c. peeled, seeded, and chopped cucumbers
1/4 c. toasted pine nuts
2/3 c. cooked corn, cut off the cob
1/4 c. cider vinegar
1/2 c. olive oil
Salt and pepper to taste
Combine feta, tomatoes, cucumbers, pine nuts, and corn in a bowl. In a separate bowl combine oil and vinegar. Drizzle vinaigrette over other ingredients and toss to combine. Add salt and pepper to taste.
It's really super simple. You can also add a lettuce leaf and stuff it inside a pits for a quick sandwich. I like to grill the pita first so there's a little more crunch to the sandwich.