A clasp for quickly attaching your cable lock to your bike frame for easy carrying while you ride. Designed as a replacement for the clasp on a Giant brand 12mm-diameter cable lock.
Animation of how it clips onto the bike: http://i.imgur.com/lrpud74.gif
I printed mine on a MakerBot Replicator 2 using PLA, with supports and raft at 0.3mm resolution. I used six 2M machine screws and nuts to secure the two halves together, and the screw that was part of the original clasp to secure the center.
I've included the parametric OpenSCAD file, which should make it easy for you to adapt to your lock if needed.