MatterControl - MatterControl is a free, open source app that lets you organize and manage your 3D prints.
Toggl - Toggl is an online time tracking tool. It features 1-click time tracking and helps you see where your time goes. Free and paid versions are available.
Slic3r - STL-to-GCODE translator for RepRap printers Here comes Slic3r! Its features are: - speed
Harvest - Simple time tracking, fast online invoicing, and powerful reporting software. Simplify employee timesheets and billing. Get started for free.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
RescueTime - Time management software that shows you how you spend your time & provides tools to help you be more productive.