In my previous college class, I was shown an OS called Tsurugi. Tsurugi can be downloaded from their main page at https://tsurugi-linux.org. It is named after a legenary Japanese double-bladed sword used by ancient monks which might be something similar to the image below.
For a while now, I have had issues with Sift Workstation in Qubes OS VM. You can read about my issue on the sift-cli github
Configuration Arch Linux + i3wm as a forensics workstation and lab computer. Part 3 of the series.
pfsense probably is the most well-known used used open-sourced Linux firewall appliance in used today. It provides an easy to use web page GUI and installation is extremely easy.
I ran across Hacking&Coffee's post Red Team Laptop & Infrastructure (pt 1: Architecture) during research for SIFT Workstations and virtual technology.