Comodo specialise in a range of services and products\solutions such as SSL certificates and authentication. Comodo also provide a very well known and free firewall for home users.
Filseclab provide personal firewall that is free for use.
Fortinet are a specialist in UTM firewalls of all sizes and also have a free firewall bundled with other malware protection features for home users. The software is known as FortiClient.
Look n Stop Firewall provide a personal firewall.
Online Armour by Emsisoft is a free firewall for home computers and laptops.
privacyware provide a free firewall.
SoftSphere Technologies offer a personal firewall known as DefenseWall.
Sunbelt who sell a range of security products offer a personal free firewall for home users.
ZoneAlarm is a security vendor owned by Checkpoint who are also a security vendor. ZoneAlarm provide an excellent free firewall for home users.