Over at the Volokh Conspiracy, Sasha Volokh quotes the lines from Shakespeare about the soothsayer warning Caesar of the Ides from Act I, Scene 2.  Great and timely.  But I like more the later exchange from Act III, Scene 1, when Caesar, on the Ides of March, sees the soothsayer, and says:

CAESAR:

[To the Soothsayer] The ides of March are come.

SOOTHSAYER: 

Ay, Caesar; but not gone.