PSFilterPDN is a free Paint.NET plugin which enables the program to run Photoshop-compatible filters plugins (.8bf files).

There's no automatic installation, but the process isn't exactly difficult. All you have to do is unzip the download, and copy PSFilterPdn.dll and PSFilterShim.exe to the Paint.NET effects folder (probably C:\Program Files\Paint.NET\Effects).

Any .8bf files you'd like to try can now be copied at any time to the same folder.

Restart Paint.NET, open the Effects menu, click the new "8bf Filter" option and you should see a tree of whatever filters you've installed. Select something, click "Run" to launch it, and you'll be able to manipulate the current image, just as though you're using any built-in Paint.NET effect.

If it's not convenient to place a filter in Paint.NET's folder, then you can alternatively place a shortcut to its real location, or add that location to a "Search Directories" list.

Please note, while the plugin worked well for us, the developer warns "many filters should run although some may have issues".

Version 1.0.6.0:
     - Fixed an alpha channel bug with the Dfine 2 filter from the Google Nik Collection.
     - Fixed a bug with the Vizros 4 Lake filter.
     - Various other performance improvements.