Oliphaunt

Because it's one of my favorites...

Grey as a mouse,
Big as a house,
Nose like a snake,
I make the earth shake,
As I tramp through the grass;
Trees crack as I pass.
I walk in the South,
Flapping big ears.
Beyond count of years
I stomp round and round,
Never lie on the ground,
Not even to die.
Oliphaunt am I,
Biggest of all,
Huge old and tall.
If ever you'd met me,
You wouldn't forget me.
If you never do,
You won't think I'm true;
But old Oliphaunt am I,
And I never lie.
--Tolkien