"Carpe diem." (Sieze the day.)
"Duc, Sequere, aut de via decede." (Lead, follow, or get out of the way.)
"Deus Vult." (God wills it.)
"Every man dies. Not every man really lives." -Mel Gibson, "Braveheart"
"The way to a man's heart is through his ribs." 
"Old age and treachery will triumph over youth and skill."
"Keep the books -- burn the censors!" 