I do. I have one that says how to care for wool, and a couple with my name.
I don't always use them, but often. One thing I like about them is that if the garment is passed on (like childrens items often are), that the new owner will be able to see that it was hand made, and by whom.
I posted photos of mine in a thread here once, and the place I got them from. It's somewhere in the archives.
KnittingHelp Queen Bee
It is not because things are so difficult that we do not dare; it is because we do not dare that they are difficult.