Yoggie will offer its tiny Linux-based hardware firewall in the PCMCIA ExpressCard form factor. Available next month, the Gatekeeper Card Pro firewall fits completely inside host laptops, and runs 13 different applications aimed at keeping Windows-based PCs safe from viruses, spam, malware, and other security threats.

An Israeli startup has squeezed a complete hardware firewall into a USB key. The 'Yoggie Pico' from Yoggie Systems runs Linux 2.6 along with 13 security applications on a 520MHz PXA270, an Intel processor typically used in high-end smartphones.

Linux security device maker Yoggie has launched a knowledge base to support its small-formfactor ARM-based hardware firewall products. The Yoggie Knowledge Base uses an FAQ (frequently asked questions) format, and currently has about 40 questions that reveal interesting details about Yoggie's tiny firewalls.

Yoggie's innovative Yoggie Pico may well be the first hardware firewall that is truly practical for mobile workers running Windows-based computers. The device appears to work well, except for a simplistic web-based user interface that may not satisfy technical users.

A packet filtering firewall, designed to regulate incoming and outgoing packets from a network or an operating system, is akin to security personnel guarding the entrance to a commercial or residential property. Such a system has very little authority, unless given additional powers, in what applications inside the operating system or network are able to do.

SmoothWall Express 3.0 is an open source GNU/Linux firewall which is security-hardened and freely downloadable. By design, it has minimal hardware requirements and a small footprint.

Here's a device that started out as a firewall and ended up as a powerful embedded development platform. It's based around an ARM CPU and includes an SDK to let you develop your own tools.

Endian Firewall Community is a free edition of Endian Firewall, a security-focused Linux distribution developed by Endian S.r.l., a Linux solutions provider based in Bolzano Italy.

Yoggie Security Systems has today released the source code for its Linux-based mini-security computers to the developer community, and aims to release the source code to most of the applications on the Yoggie Gatekeeper system in due course.