Pandan
Passive time tracker that sits in the menu bar. You can see how long you've been in a 'session' at your computer without needing to manually start/stop sessions. It's a good mindfulness tool for working
Dato
Quick access to mini calendar and upcoming events in your menu bar + Lots of customization settings
One Thing
Put a single task or goal in your menu bar, or any text or link
Apps — Sindre Sorhus
Lots of free, simple, well-designed, and useful mac apps by this developer