Inspired by Kinekt Design‘s Gear Ring here’s a try at a rendered gear cufflink (the center gear would be fixed, while the plate with the other gears revolves around it) :

© crackedrock.at

© crackedrock.at

Speaking of rings, I recently stumbled upon a crowdfunding campaign for a ring-shaped music (MIDI) controller, which seems like a pretty cool gadget to me (although, to be honest, I still don’t know how a violinist like me could use it for making music).

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