You'd expect to find a ring in a box, but what if you found a box in a ring? What works of sci-fi....?

Question

What works of sci-fi include hyperspace "pockets", kind of like the ones on your jeans but hidden in a piece of jewelry or some other personal item, like a ring where you push down on the jewel and a spacetime rift opens up....and you pull out a cigar box, take out a stogie, close the box, and put it back in your ring?

Anything like that? Where can I find it?

Answer 1

What are you on and where can I get some?

Answer 2

Learn how to make one here!!!

http://www.magictricks.com