Here's a tip for you all:
My work area is surrounded by plumbing and household appliances, so I got some nice noise-canceling headphones. Now that I've started using them, I discovered that they can actually inject noise. I was wrestling with a constant low-frequency noise, something like a hiss taken down three octaves, when it occurred to me that the headphones might be at fault.
Sure enough, when I turned off the electronics in the phones the noise moved from inside the phones to outside. It was the fan noise from my computer.
Interesting, thank you. Can't say I've ever been tempted myself.