've made a number of FF filters for use with Photoshop and After Effects and have them on my web site,
http://www.gwhite.us/design/ Navigate to the image filters page. The Blur Threshold filter in particular is very useful for reducing noise and jpeg artifacts without blurring edge detail. There is nothing in Photoshop that gives you this level of control without the use of a mask, and I used this daily in production work. All the filters here are compiled in filter factory for use on a Windows system, but the dowmload includes the code for each filter so Mac users may make them.
