Porteus Kiosk Edition Is an Operating System Based on Slackware and Firefox
Porteus 3.1 (Kiosk Edition) is based on Slackware 14.0 and relies on Linux kernel 3.12.20 and Firefox 24.0. It's a 32-bit system, which is entirely locked down to prevent tampering with any of the components (including the browser).
“This distribution release includes bug fixes, software updates and new features. At a mere 50 megabytes, the Porteus Kiosk Edition ISO includes just the libraries and utilities required to run Firefox in a secure environment, making this a perfect fit for kiosks and other web terminals.”