Most people have seen all of the below, but perhaps not all in one place, at one time, and considered in conjunction. So, mix 'em, match 'em, trade 'em with your friends:
I am that I am.
Tat tvam asi.*
The Tao of which one can speak is not the true Tao.
Before Abraham was, I am.
Existence precedes essence.
The world is all that is the case.
*Thou art that.