OpenVPN is a robust and highly configurable VPN (Virtual Private Network) daemon which can be used to securely link two or more private networks using an encrypted tunnel over the Internet. OpenVPN's principal strengths include wide cross-platform portability, excellent stability, support for
... [More] dynamic IP addresses and NAT, adaptive link compression, single TCP/UDP port usage, a modular design that offloads most crypto tasks to the OpenSSL library, and relatively easy installation that in most cases doesn't require a special kernel module. [Less]
Celestia is an OpenGL-based 3D space simulation for Unix and Win32 that lets you travel through the solar system, to the stars, and even beyond the galaxy. Visit over 100,000 stars, 100 solar system bodies, and all known extrasolar planets.
Gravit is a gravity simulator which runs under Linux, Windows and Mac OS X. It's released under the GNU General Public License which makes it free. It uses Newtonian physics using the Barnes-Hut N-body algorithm. Although the main goal of Gravit is to be as accurate as possible, it also creates
... [More] beautiful looking gravity patterns. It records the history of each particle so it can animate and display a path of its travels. At any stage you can rotate your view in 3D and zoom in and out. Gravit uses OpenGL with Lua, SDL, SDL_ttf and SDL_image. [Less]