Air purifiers seem like a good idea especially if you live in a big city like New York, but how do you know if they are having any effect?
This purifier from Coway lets you know with a little glowing circle in the upper left corner. If it's blue you can breathe easy, but as it changes to purple and then red, it warns you about increasing levels of pollution in the air passing through it.
The AP-1008 appears to be a pretty powerful device, with a multistage HEPA filter and a wide array of automated controls. It can even be set to work automatically, turning itself on when the pollution level becomes elevated.
The biggest obstacle I see is the $499 retail price. But what price can you put on breathing clean air?