Let's here your best paradoxes.
A law student agrees to pay his teacher after (and only after) winning his first case. The teacher then sues the student (who has not yet won a case) for payment.
If Pinocchio said my nose will grow now it would cause a paradox
step one to wreck spacetime: go back in timestep two: kill your grandfather.step three: uh, try and escape the universe before it overloads with you dying and un-dying all the time
Wouldn't that create a space-time loop that would be inescapable and you would repeat without realizing it? That is how I view the outcome of the Grandfather paradox (related is the Hitler paradox, also very interesting).