Fait mathématique: 2308 is the number of conjugacy classes of the alternating group A_{29}.
Culture générale: 2308 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Date historique: April 26th is the day in 1478 that the Pazzi attack Lorenzo de' Medici and kill his brother Giuliano during High Mass in the Duomo of Florence.