I get easily distracted when I work, so I'm the sort of person who craves silence. I also can get disturbed pretty easily when I am sleeping. Unfortunately, my house-mate is basically always watching TV, very loudly, and he stays up at odd hours so the racket can easily continue all night. He's a great guy otherwise. However, this noise was becoming a major problem for me both in terms of lost work productivity during the day and in terms of sleep quality at night. Then the Dohm sound machine entered my life.
It makes this whooshing white-noise sound, which is adjustable to some extent. It's a very unobtrusive noise. The sound machine can effectively wipe out quite a bit of noise as long as the sounds are in the mid and upper tonal range. I found that it was unable to block the heavy bass sounds of the stereo's subwoofer, but now I turn that off when I go to sleep and the sound machine very effectively blocks what can only be described as a TV set on blaring levels. It's also wonderful for sleep because I don't even hear a lot of the jarring sort of sounds that used to wake me up at night (like fire truck sirens).
The only cautionary note on the sound machine is that it generated a mild plastic smell for about the first 24 hours of use. I moved it into the carport and ran it outside for a day, then everything was fine.
This thing has had a significant positive impact on my life. I'm using it right now as I write this and it's creating a pleasant little sound bubble of productivity. Thank you to Tim Ferris for letting me know about this handy little device in his book, Tools of Titans.