Dyson really hates dirt, to the point that it's now come up with a new bladeless fan that can also filter out ultrafine airborne particles -- including viruses, bacteria and pollens -- that are as tiny as 0.1 microns. The aptly-named Pure Cool (AM11) closely resembles Dyson's other fan towers, with the notable difference being the cylindrical glass HEPA filter around the base. After 450 prototypes, the company claims that this filter removes 99.95 percent of ultrafine particles, and it's good for up to 4,382 hours or about six months of continuous use. In other words, if you use the Pure Cool for 12 hours each day, then you'll only need to replace the filter after a year. Of course, it's hard to say whether it'll last just as long in smoggy Beijing, which is where Dyson cleverly chose to do the global launch for the Pure Cool.