Diet Coke - the Pepsi's too sweet for me! YUCK! And I prefer it from a bottle - cans give it an odd taste (probably metallic) & the fountain stuff tastes odd, too. Years ago it was because they were still using saccharine in it, not aspartame because it broke down in the heat & over time. I don't know if that's still true, but it still taste different than from the 2 liter bottle.