Anythinjg with a HEPA filter will clean the room and do it better than ionic air cleaners.
According to Wikipedia: http://en.wikipedia.org/wiki/HEPA_filter
"A high efficiency particulate air or HEPA (IPA: /ˈhɛpə/) filter is a type of high-efficiency air filter.
HEPA filters can remove at least 99.97% of airborne particles 0.3 micrometers (µm) in diameter. Particles of this size are the most difficult to filter and are thus considered the most penetrating particle size (MPPS). Particles that are larger or smaller are filtered with even higher efficiency.
HEPA filters are composed of a mat of randomly arranged fibres. Key metrics affecting function are fibre density and diameter, and filter thickness. The air space between HEPA filter fibres is much greater than 0.3 μm. The common assumption that a HEPA filter acts like a sieve where particles smaller than the largest opening can pass through is incorrect. Just as for membrane filters, particles so large that they are as wide as the largest opening or distance between fibres cannot pass in between them at all. But HEPA filters are designed to target much smaller pollutants and particles are mainly trapped (they stick to a fibre) by one of the following three mechanisms:
Interception, where particles following a line of flow in the air stream come within one radius of a fibre and adhere to it.
Impaction, where larger particles are unable to avoid fibres by following the curving contours of the air stream and are forced to embed in one of them directly; this increases with diminishing fibre separation and higher air flow velocity.
Diffusion, an enhancing mechanism is a result of the collision with gas molecules by the smallest particles, especially those below 0.1 µm in diameter, which are thereby impeded and delayed in their path through the filter; this behaviour is similar to Brownian motion and raises the probability that a particle will be stopped by either of the two mechanisms above; it becomes dominant at lower air flow velocities.
Diffusion predominates below the 0.1 μm diameter particle size. Impaction and interception predominate above 0.4 μm. In between, near the 0.3 μm MPPS, diffusion and interception predominate.
The initial filter air flow resistance and final filter air flow resistance are typically measured as pressure drop across the filters."
There are vacuum cleaners like the Dyson and room ventalators that all have HEPA filters in them.
Here are just a few places where you can find HEPA filters.
http://www.overstock.com/search?SearchT ... 16320&fp=f
http://www.airpurifiersdirect2u.com/ind ... nAod7n5KWQ
http://www.sears.com/shc/s/s_10153_1260 ... 515x00001a
http://www.oreck.com/upright-vacuum-cle ... code=DB479
HEPA filters are not a gimic, but I think the ionic air cleaners are.
According to Wikipedia: http://en.wikipedia.org/wiki/Electrostatic_precipitator
"An electrostatic precipitator (ESP), or electrostatic air cleaner is a particulate collection device that removes particles from a flowing gas (such as air) using the force of an induced electrostatic charge. Electrostatic precipitators are highly efficient filtration devices that minimally impede the flow of gases through the device, and can easily remove fine particulate matter such as dust and smoke from the air stream."
But, those are primarly for industrial applications. They inspired the ionic air fresheners, but those are not as good.
According to Wikipedia: http://en.wikipedia.org/wiki/Air_ioniser
"Air ionisers are used in air purifiers, though they are not efficient in this respect. Airborn particles are attracted to the electrode in an effect similar to static electricity. Heavier combined particles may precipitate (fall) out of the air.
The use of negative ions continues to be a less accepted mainstream therapy in Eastern Europe and the Far East than in Western Europe or the United States although problems with nosocomial infections (hospital acquired "super-bugs") have led the National Health Service (NHS) in the UK to do extensive research into the effect of negative ions on this area of hygiene. Recent SARS outbreaks have fueled the desire for personal ionizers in the far east, including Japan (where many products have been specialized to contain negative ion generators, including toothbrushes, refrigerators and washing machines). There are no specific standards for these devices."