Fatto generale: 708 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Fatto matematico: 708 is the maximum value of n so that there exist 4 denominations of stamps so that every postage from 1 to n can be paid for with at most 12 stamps.
Trivia: 708 is an uninteresting number.
Data storica: December 8th is the day in 1991 that the leaders of Russia, Belarus and Ukraine sign an agreement dissolving the Soviet Union and establishing the Commonwealth of Independent States.