Originally Posted by ImTheDevil

One thing that many people don't know, as a side tidbit - a bad or corroded chassis ground for the battery can actually accelerate the wear on your CV joints - when the ground wears down, a pathway through the mechanicals of the drivetrain supplements the grounding circuit of the electrical system. As the CV teeth begin to mesh, there's an arc-welding effect between teeth, where current will arc between teeth, eroding them. Over time this wear eventually causes the joint to fail. Get some braided steel cable and add a few grounds around the engine and engine bay, each daisy-chained off the last in a loop, or radiating out from the battery ground to various ground points. It can help you save your CV joints, and can also rejuvenate the electronics of your car - you may find a slightly smoother idle, quicker starting, and more precise control of the car's electronics, which can give a small bump in economy as well.

It's one of those things that I'd have never thought up until a friend of mine (17 year ASE mechanic) explained it out. Pretty cool and interesting.