Granted. You immediately start doing all the things you've been putting off for years.
You become so engrossed in completing every task you've ever said you'd like to do one day that you forget to sleep.
You find yourself completing minor tasks you'd forgotten you'd ever even meant to do in the first place. You stop bathing, you stop eating. Every waking moment is dedicated to completing everything you ever offhandedly mentioned that you might like to do one day.
Eventually you find yourself trying to complete impossible tasks you had only fantasized about and die tragically attempting to fly off a building like Superman.