Negative ion generators

[jakematic]

Johnny mentioned these in the air cleaning plants episode and I have a pretty good size air purifier/generator in the living room.

What I'm looking for is smaller units for around the house - specifically the bedroom and office.
There is a lot of bad energy in this area and we can use all the negative ions we can get.

Has anyone got any suggestions or models they use ?
I'm looking at getting 4 of these http://www.amazon.com/Professional-Grade-Plug-In-Adjustable-Ionic-Purifier/dp/B005E1CW9W
but the price.... egads.

Appreciate any input. Thanks- Jake

p.s - Yes, I know they can emit ozone. It's all about adjustment and the benefits far outweigh 

[Johnny-Max]

I can even afford that 
What is you put several in the air intake on your central air system?

[jakematic]

Want to try a MUCH cheaper option?

PERFECTION ! Thank you thank you thank you.

Gonna order a dozen - I like backups 

What is you put several in the air intake on your central air system?

There are units designed to slot right into the intake after the filter.
That's going on my next house's system, along with an air exchanger and humidifier.

Think I have a better design that the other exchangers I've seen - and way less expensive too.