I N S I D E ³ is a cube that contains a 3D labyrinth where you will have to guide a little ball to its destination. Explained like this, it seems rather easy... What I didn't tell you is this: you cannot see the inside of the cube. Thankfully, there's a map indicating what path the ball must follow to reach its destination. The plan indicates 7 different paths; one for each level you'll have to guide the ball through.
The product comes in six different versions of increasing difficulty, adding trapdoors and dead ends as the difficulty rises.
Here's what the cube looks like:
Here's an image with a transparent case to give you an idea of what the inside looks like (of course there won't be a transparent version as it would be too easy):
If you get stuck, you can always disassemble the cube and start over (except for the Vicious and Mortal cubes that can't be disassembled).
If you're interested in this product, you can help funding it via the French crowdfunding service Ulule. If you fund them € 25 or more, you'll get your own cube once the funding is over.
Here's finally a video of an I N S I D E ³ cube in action:
Special thanks to Bruno Borges for telling me about this ;-)