I have once, when I was a tiny colt. I don't remember much of it, but my daddy tells me that my favorite part was helping him sell apples at our Apple Stand in the Canterlot Market. Apparently, I got him a lot of business that day, because I was just so gosh darn cute and happy lookin' suckin' on an apple that everypony wanted to come tell my daddy just that, and then he talked them into some apples. Heck of a salespony, my daddy. He could sell a zap apple to a zap apple tree...after picking that same apple from the tree.
Keep those questions a-comin, pony folk! I feel right happy when I answer y'alls' questions. You wouldn't want to make me sad, now would ya?