Can someone tell me a little about negative ion air purifers, like the one's advertised by Sharper Image?

sharper image has consistently been given bad reviews by consumer reports. shaklee has a very good one (and no, i'm not a distributor). it works by ionizing dust particles (in simple terms, it makes dust particles heavy so they fall to the floor instead of floating around waiting to be inhaled). you could also get consumer reports' latest reviews on air purifiers. the good ones are not cheap but they're worth it.

If you smoke inside forget the ionic breeze, the filter pulls the smoke in and it sticks to the outside. Makes a horrible sticky mess. Got a brown nasty one in the corner that I haven't used in a long time.

If you smoke outside it's great.