Mendo Grape Kush tastes amazing... and despite its name, it tastes very citrus with some skunkyness to it. (probably from the Grapefruit genetics in its lineage).
Tangie is also very tasty: I had a small phenohunt and all of the phenos tasted like oranges, however some were more of a buttery/carmel/sweet candy orange, and some were more of a Bitter Orange Rind/almost Garlic smell.
Blue dream is one of my personal favorites for the flavor which is sort of a citrus, incense type smell.
Grand Daddy purple/Purple Urkle/Mendo Grape all have a more grape, berry type flavor to them with a hint of floral. Some of my favorite purples strains by a long shot!