Comodo Personal Firewall is definitely my favorite firewall on the market right now. A large part of that reason is because you can download it and receive an activation code for FREE!
Besides for the reasonable cost ( ;) ) it is also loaded with features and customizability, both of which are extremely important to me. Sometimes it is nice to have software that you don’t have to configure but it is also nice to have choices. Comodo kind of has the best of both worlds because it worked just as it should without configuring anything but if you feel the need to do some tinkering then the nice list of settings are awaiting your clicks.
Some people wonder whether Comodo slows down your Internet connection but that has not happened in my experiences with it. I just installed it on another computer and tested the speed to see that it was almost exactly the same (about 5Mbps). Maybe it does happen to some people but it seems to work good for me. I have taken some screenshots below so that you can see the different configuration panels before downloading it: