Just rum and coke.
I know how it will affect me and how many I can drink (4-5, depending on how loosely the rum was poured).
I got turned on to Lava Flows when I was in Maui; it's basically a Pina Colada with strawberries belnded with rum to make a sort of syrup that makes the "lava". Yummy.
Also, a bartender friend made Gorilla Milk for me like, 7 years ago, and I haven't been in a bar since that knows how to make it although most will make it as long as I explain it; the way SHE made it was light and dark rum, banana liqueur and half and half.
I have seen other recipes for it that call for coffee liqueur or creme de cacao but I know my friends recipe didn't have those in it.