Your results contain 9 solutions with the following criteria :

Firewall
Solution Smile rating Users rating Popularity
Ferm No rating No rating
11%   Popularity on the site
Firewall Builder No rating 2.2 Visitors
14%   Popularity on the site
IPCop IPCop 3.2 Smile 4.0 Visitors
9%   Popularity on the site
netfilter NetFilter 4.5 Smile No rating
36%   Popularity on the site
NuFW No rating No rating
9%   Popularity on the site
ShoreWall No rating 3.5 Visitors
13%   Popularity on the site
Uncomplicated Firewall No rating No rating
14%   Popularity on the site
pf (Packet Filter) 3.5 Smile No rating
16%   Popularity on the site
pfSense pfSense 3.5 Smile 3.7 Visitors
41%   Popularity on the site