(this is from a nike ad from the early 90's)

Too often we are scared.
Scared of what we might not be able to do.
Scared of what people might think if we tried.
We say no when we want to say yes.
We sit quietly when we want to scream.
And we shout with the others,
When we want to keep our mouths shut.
After all,
We so only go around once.
There’s really no time to be afraid.
So stop.
Try something you’ve never tried.
Risk it.
Enter a triathalon.
Write a letter to the editor.
Demand a raise.
Call winners at the toughest court.
Throw away your television.
Bicycle across the United States.
Try bobsledding.
Try anything.
Speak out against the designated hitter.
Travel to a country where you don’t speak the language.
Patent something.
Call her.
You have nothing to lose.
And everything
Everything to gain.

Just do it.