I've had a couple of lucid dreams involving a mirror and below is one from my notes:

"I went to the large dresser mirror to see what would happen if I looked at it or touched it.
I looked in the mirror, saw myself.. and I looked just like me. I put my hand to the mirror and nothing happened.
I started to sing a song (I can't remember what it was) and the mirror began to act like a funhouse mirror.
My face became distorted.. it became wider, then longer.
It was great fun morphing my face and I did that for a few minutes."
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