Like pz said, slice them very thinly along with some red onion and minced garlic. Then stir to combine and give the mixture a bath in cider vinegar. Add a little salt and pepper to taste. Much, much better than cucumbers IMHO
Another good use is to de-seed them and chop/dice finely along with yellow onion, sweet peppers, a few jalapenos, black olives, garlic and a few de-seeded ripe tomatoes. Stir and "tighten" with a few teaspoons of EVOO and a little salt. This is a modification of pico de gallo or "fresh salsa" that is great for dipping with corn chips. I also like to use it in omelettes. You can adjust the heat level by the number of jalapenos you use and whether or not you remove the seeds and veins from them.
Hub