"Sigma File Manager" is a free, open-source, quickly evolving app
TagSpaces is an offline, open source, document manager with tagging
The break time reminder app
Open-source productivity booster with a brain
Self hosted FLOSS fitness/workout, nutrition and weight tracker
Desktop soundscape application
Linux for content creation, web scraping, coding, and data analysis.
To-do manager, notepad, RSS reader...
A windowed/full-screen countdown timer.
Terminal based markdown note manager
The smartest way to work on your computer
Set styles to words and create a Table of Contents in a click
A simple reminder Gui for Linux using wxpython
The Markdown-based note-taking app that doesn't suck
Create sticky notes, to-do list, journals & reminders all in one app
Plain-text file notepad with markdown support and ownCloud integration
Open Source Productivity App
An Academic Literature Suite
Work productivity/efficiency analytics, work-life and time manager
Tiny reminder with very simple user interface and no installation
Desktop client for url shorten services like goo.gl,bit.ly,tinyurl