Really takes TB filters to another level! Rated 5 out of 5 stars
I needed the possibility to filter emails using regular expressions. FiltaQuilla really surprised me. An amazing add-on with many options and great potential. Works flawlessly on TB 3.1.6. I am quite sure that some of the bad reviews here are the result of users not completely understanding and mastering TB filters in general and the complexity of this extension in particular.
Read my showcase review with some screenshots of FiltaQuilla here: http://digiblog.de/2010/11/26/regular-expression-mail-filters-for-thunderbird