Porteus Linux

Porteus is a complete linux operating system that is optimized to run from CD, USB flash drive, hard drive, or other bootable storage media. It’s small (under 300Mb) and insanely fast which allows you to start up and get online while most other operating systems are left spitting dust. Porteus comes in both 32 & 64 bit and aims to keep on the bleeding edge.

Appears to be based on Slackware and doesn’t have a focus on privacy like Tails, but more on speed and usability.