UXPin + Slack - Keep tabs on design projects in Slack
i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
StatusOk (Open source) - Get notified through Slack/email when your website is down
dwm - dwm is a dynamic window manager for X. It manages windows in tiled, monocle and floating layouts. All of the layouts can be applied dynamically, optimising the environment for the application in use and the task performed.
Attentive - A marketing channel, built for retail & e‑commerce
Openbox - Openbox is a highly configurable, next generation window manager with extensive standards support.