Alpine Linux
Alpine Linux is a community developed operating system designed for routers, firewalls, VPNs, VoIP boxes, containers, and servers. It was designed with security in mind; it has proactive security features like PaX and SSP that prevent security holes in the software to be exploited.
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FunOS
FunOS is an Ubuntu-based Linux distribution which features the JWM graphical user interface. The project is intended to be more lightweight than official Ubuntu community editions while providing the same application compatibility and hardware support.