Alex WikiMessenger Bot - A Wikipedia bot for messenger
On-Screen Ruler - lightweight, free, semi-transparent ruler
botwick - Build your own SMS-based text bot
Bluegrams Screen Ruler - A lightweight and configurable ruler tool for Windows Desktop.
Sensay for Slack - Get advice from a helpful human, now available in Slack.
Pixus - Pixus is an AIR pixel ruler application, a handy tool for web and interface designers.