By coincidence I was given one of these just this week... the kumquat!

Given to me by one of the office staff at elementary school. Had no idea what it was at the time, but in the fine Japanese tradition of taking what is given you to be polite, I ate one. Not bad. The sweet/sour thing was interesting. The JET Programme brings continuous new experiences :)

Taste Test: Kumquat - Boing Boing:

"Kumquats are full of vitamin C and potassium; in Japan, it is called kinkan, also the name of a popular over-the-counter drug brand that makes remedies for sore muscles, sore throat, and mosquito bites."