Good Riddles

Question: Had by few but treasured by all,
I'm on the inside and outside and I make men fall.

What am I?

Question: Looking at my face, I'm no more than six.
Look at the rest of me and I'm 21.
You'll see my twin and me in Las Vegas.
Say my name and you'd be uttering a threat.

What am I?

Question: To give me to someone I don't belong to is cowardly, but to take me is noble.
I can be a game, but there are no winners.

What am I?

Question: 100 feet in the air, yet its back is on the ground.

What is it?

Question: I turn polar bears white
and I will make you cry.
I make guys have to pee
and girls comb their hair.
I make celebrities look stupid
and normal people look like celebrities.
I turn pancakes brown
and make your champagne bubble.
If you squeeze me, I'll pop.
If you look at me, you'll pop.

Can you answer the riddle?