JVC HA-NC80 Consumer Headphones

I bought these headphones as I work in the office with fairly noisy air conditioning system which was getting a bit annoying after a while. I didn't want to spend £150+ on Bose headphones, so went for the JVCs. It turned out to be excellent choice. The headphones noise-cancelling feature works really well with air-conditioning noise. It really is like magic-you flip the switch and the noise is gone :) I tested it with other noise sources (tube, train, street noise) and can confirm that it seems to be mainly working for rather low frequencies, so don't expect all unwanted noise to disappear. It does help on the train/tube. I only use it on "wide" setting as it seems to be blocking wider range of noises. The headphones use a single AAA battery, which lasts for ages (unless you forget to switch them off-the 'power on' switch is manual).
They are fairly comfortable although you will need to give your ears a bit of rest every hour or so :) The sound quality is excellent, just as you would expect of JVC. Build quality is excellent. You also get a nice fake-leather pouch to carry the headphones around.
For the price you can get them on ebay (or even if you were to buy them new), you would be hard pushed to find a better choice of noise cancelling headphones. I can definitely recommend them.