General Knoppix support for those who've read the FAQ at the Wiki
FORTINET FORTIGATE 40F Next GEN Firewall Security Unregistered (FG-40F)-Open Box
$140.79
FORTINET FortiGate60F+1YR Forticare UTP Unregistered(FG-60F-BDL-950-12)-Open Box
$254.25
Fortinet FortiGate 60F | 10 Gbps Firewall Network Security EXPIRED (FG-60F)- New
$251.99
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
Watchguard Firebox T35 Network Security Firewall Appliance MS3AE5
$45.00
Palo Alto PA-220 Next-Gen Firewall
$57.19
Cisco ASA5512-X Firewall Adaptive Security Appliance 9.12.4(48) Base License
$49.00
Fortinet Fortiwifi 60D FG-60D Security Appliance Firewall / VPN w/ AC Adapter
$34.97
SONICWALL TZ270 Network Security Base Appliance Only (02-SSC-2821) - Open Box
$186.87