Using knoppix on laptops. LCD screens, APM, PCMCIA ...
Firewall pfSense 2.7.2 Release 8GB Memory - Dual NIC 1 GB - 120GB intel SSD
$105.77
OpnSense PFSense Firewall - Enhanced Cooling - N100 - 2.5 Gbe 6-port - US Seller
$380.00
OpnSense PFSense Firewall - 12th Gen N100 - 2.5 Gbe - US Seller - Multi Options
$299.99
Palo Alto PA-220 Next-Gen Firewall 750-000128-00A w/ Power adapter
$68.00
Cisco ASA5506-K9 ASA 5506-X Network Security Firewall
$40.00
Ubiquiti Networks Unifi Security Gateway Pro 4 USG-PRO-4
$100.00
FORTINET FORTIGATE 40F FG-40F FIREWALL SECURITY
$120.00
Cisco Meraki MX84 Cloud Managed Security Firewall Appliance UNCLAIMED MX84-HW
$39.99
SonicWall TZ270 High Availability Firewall Security (02-SSC-6447) - Open Box
$211.99
Cisco Meraki MX67-HW Cloud-Managed Security Appliance - Unclaimed
$259.99