Biggest hype-worst tweak

I was wondering what everybody had found to be the biggest waste of time regarding tweaks-I've tried most-largely with satisfying results.The worst one for me was a Statmat (this months Hi-fi Choice has Jimmy Hughes still raving about the thing!)-a polythene floppy mat for sitting on top of your CD's-with weird markings-supposed to disperse static and make motherships land in your garden or something... Pure nonsense-had me pulling my hair out as it stuck in the tray constantly and my face twisted at the strain of trying to hear something/anything.....how my girlfriend laughed as she picked the thing up-you need help she remarked-I sent it back...and yet I fear I might have missed something Ben