Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy
Remember The Milk - Remember The Milk is a task and time management application for mobile devices.
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.
Scheduled tasks - GNOME GUI for configuring a users' cron (automatic jobs). Some of its features are:
Weer - A HTTP protocol debugger with Chrome DevTools frontend interface