It is taken for granted that medical technologies will advance apace in the future, permitting rapid healing and perhaps even shaping of the human body. This submission is to provide possible flavors for that medicine to come in.
A slight rustle of the wind... and it stands before you. A Unicorn, whiter and more beautiful than you ever imagined it. It has deep wonderful eyes, and you can't help but admire this creature. It came to have a look at you, and now it freely goes. You have not the heart to stop it, and it silently vanishes between the trees.
Note: unless specially needed, this encounter should never happen again.