Originally Posted by relyt

A pair of 42" bolt cutters can cut a Kryptonite chain, there is a video or two on Youtube of a guy cutting a bunch of heavy chains made for motorcycle security. He's obviously having a hard time of it, but he pulls it off.

He was able to do it because he got the chain low enough that he could brace one handle of the bolt cutters on the ground, and then push down on the other handle with his full weight. If you lock properly, you will wrap excess chain around the bike or post and not leave much slack.