1)   AstroGrav (Windows) 1.2.2
A software program that allows you to study how astronomical objects move and interact under the force of gravity. It features superb interactive 3D graphics which allow you to move around within an astronomical system, while watching how it evolves.

 2)   Universal Scientific Calculator 3
Math Functions, factorization, financal, average, regression, factorial, dates, complexes, charts, units converter, ephemerids, Euler, Simson, gravitation. Fourier Series, Pi, Solar System, many games, Molar Mass, Taylor, Bernoulli, Gamma...

 3)   Orbit Xplorer 2.0
Educational orbit and gravitation simulator for high school, college and beginning university physics and astronomy. Easily create, run, print and save a simulation. Includes 29 premade simulations with activities page in html-format.

 4)   Gravitational Lensing 1.00
With this program, one can draw images to see the effect of gravitational lensing. You can easily test the effects of several parameters by changing them and redrawing the image.

 5)   AstroGrav (Mac) 1.2.2
A software program that allows you to study how astronomical objects move and interact under the force of gravity. It features superb interactive 3D graphics which allow you to move around within an astronomical system, while watching how it evolves.