I absolutely adore fruit juice drinks. If I was a Harvest Moon character, fruit juice would make my heart meter fill instantly. Watermelon juice is my favorite right now, but I also really like peach juice. Watermelon juice (especially Minute-Maid brand) is wonderful, because the taste of watermelon just captures the essence of summer, and is the perfect summer drink for those who do not like lemonade. Peach juice is a wonderful oddity that I've never tried until recently. Naturally it tastes peachy, and it just puts you in the mood to do something fun! Plum juice is a good one to try if you're feeling adventurous. Plum juice, or at least from what I've tried, is generally sweetened a bit to counter the normally sour flavour of plums. The flavour of plums are strong, and could be overwhelming as a juice drink, therefore by sweetening it, the taste becomes more managable. Grape juice is a classic. I find that grape juice is never good enough when made from concentrate. I also find that it is best when it is chilled to be colder than usual, even iced perhaps. Cherry juice is the oddity in that it tastes better as a concentrace, usually from Kool-Aid or Crystal Light. Cherries have a rather weak flavour, so by capturing the flavour with concentrate, it becomes easier to strengthen the taste.
Thank you for reading that wall of text about juice.