Portal is a series of first-person puzzle-platform video games developed by Valve Corporation.

Celestia is a 3D astronomy program, The program is based on the Hipparcos Catalogue (HIP) and allows users to travel through an extensive universe, modeled af…

Squarespace is a SaaS-based content management system-integrated website builder, blogging platform, hosting service and domain name registrar.

Kerbal Space Program (KSP) is a space flight simulation video game.

Overdisk is a visual disk space explorer tool.

Stellarium is an open-source free-software planetarium.

DaisyDisk is a disk space analyzer for OS X.

GrandPerspective is open source software for Mac OS X used for disk space analysis.

Star Walk is an interactive astronomy guide that shows celestial objects in the exact positions on the sky above.