Must be one heck of a dose of sugar in that kumquat + lemon drink. Both fruits are very sour to the taste. Used to get kumquats all the time as fresh fruit.
On the passion fruit side, in New Orleans an alcoholic drink made famous by the Pat Obrien's Bar, is the Hurricane. Using a signature shaped glass to serve it in, it also includes passion fruit as one of the ingredients. When wandering in the French Quarter I've been in there several times. Pat Obrien's also offers party space for reserved parties. Only then the Hurricane Glass is somewhat larger. As in using a garden hose for a straw where anyone in the party can just come by, grab up a hose, get however much they can handle in their belly, and then wander off while someone else takes their place. Such is life in the New Orleans French Quarter.