Any Diet Rite is great, especially at night since Diet Rite is one of the few drinks that does not contain caffeine.
Root beer is the same, no caffeine. So diet root beer is great too. When dieting hard down the stretch i was drinking every diet drink, every flavor i could get my hands on. Root beer was great, IBC makes diet in the bottle. Throw a few in the freezer for a couple minutes then enjoy.