LINKS
 Chunk put the idea in my head to make a prefab of these chains.  I used them in an old Q1 level called Rocketroom a long time ago.  They got a minor update to Q2, but they are basically the same.

The links need care to be taken when moved.  They will produce bsp warnings sometimes because of the odd brushes, so practice before you just "pop" these into a map you have been working on for hours.

By the way, they are huge.  The linkhalf alone is 64X64X32.