IT'S MAINSTREAM IF YOU'RE UNDER 30:

Kathrin Winter carefully hangs a Christmas decoration on a fir tree standing in a pot in the corner of her store.

But the plastic stars and Christmas balls hanging on the tree are somewhat special. Instead of being made in a factory, Winter printed the ornaments herself on a 3-D printer in the 3-D store she owns together with her partner, Daniel Zimmermann.

The store, called Mr Make, opened recently smack-dab in the middle of the high street of Karlsruhe, a city in Germany's southwest.

"Most people have heard of 3-D printing," says Zimmermann, a computer scientist by trade. "But the average consumer still doesn't have a concept of what that actually means. So our idea is to make 3-D printing more accessible."

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