Creme Soda from S.Africa is best.
"In South Africa and Zimbabwe, cream soda is sold under the label Sparletta Creme Soda, a product of the Coca-Cola company. It is green in color, with a rose/floral taste.
In South Africa, Creme Soda is often referred to as the "Green Ambulance" (predominantly by students), as it is believed to alleviate the effects of hangovers. Creme Soda is also used as a mixer with cane spirit (an inexpensive alcoholic beverage distilled from fermented sugarcane). This is commonly known as a "John Deer" (cf. John Deere and its green logo), "Cane Train", or "Green Mamba". Cane spirit is chosen due its ability to go relatively unnoticed."
http://en.wikipedia.org/wiki/Cream_soda#Africa