Seeing one on a woman's low back is probably the sexiest for me. Although, that could have something to do with it meaning I have a view of her backside and she's probably bending over which is why I can see it in the first place.

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Put me on wheels and I'll turn tricks.

Clever? Nah, I ran out of that years ago. But if you find this, let me know, k?
"The road goes ever on..." ~ Tolkien

In memory of my friend skip...
Go then, there are other worlds than these