My mom always put an orange in the toes of our stockings and a handful of nuts - pecans, walnuts, hazelnuts, etc.
My mom was also a dentist, so we always got a new toothbrush, a tube of toothpaste, and a container of dental floss in our stockings.
Then she'd round it out with fun things. When I was a kid/teenager it was like Manda described - socks, lip gloss, a gift certificate to the record store (now it would probably be an iTunes gift card!), that kind of thing. As I got older it was things like little kitchen gadgets, scarves, still fun socks, etc. But always with the orange, the nuts, and the tooth stuff.
Funny, I used to roll my eyes every year, but now that she's gone, I really miss getting my new Christmas toothbrush.
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