If you're a teensy-weensy bit anal about cleanliness of makeup applicators and brushes (which you should be, really) then Clinique's Antibacterial brushes will satisfy your inner Monica.
For those who can shop there, Sephora also make a similar set of brushes which are just as clean but not half as pricey.
Clinique Waterproof Mascara | Prescriptives Curvilinear Cheek Brush
I actually recieved the bronzer/blender brush this morning, about 20min before reading this post (it's the large one in the photo) although I had no idea it has "antibacterial" properties. I wonder how they achieve this?