General Knoppix support for those who've read the FAQ at the Wiki
FORTINET FortiGate60F+1YR Forticare UTP Unregistered(FG-60F-BDL-950-12)-Open Box
$254.25
SonicWALL TZ300 Network Security Appl FirewallRouter5pt 01-SSC-0215TransferReady
$45.00
Firewall pfSense 2.7.2 Release 8GB Memory - Dual NIC 1 GB - 120GB intel SSD
$99.77
Palo Alto PA-220 Next-Gen Firewall 750-000128-00A w/ Power adapter
$68.00
Netgate SG-3100 pfSense Security Gateway Firewall Appliance w/Power Adapter
$150.00
Dell SonicWALL TZ300 Firewall Appliance Transfer Ready - NO AC
$24.98
Palo Alto PA-220 Next-Gen Firewall
$57.19
OPNsense six-port Gigabit router/firewall on Lanner FW-7535 hardware
$69.00
Fortinet Fortiwifi 60D FG-60D Security Appliance Firewall / VPN w/ AC Adapter
$34.97
Fortinet Fortigate FG-61E Firewall Network Security Appliance ATP Bundle 1 years
$299.99