Gnac – Open Source Audio Convesion

Gnac (GNome Audio Converter) is an easy to use audio conversion program. It is designed to be easy and powerful. It provides easy audio files conversion between all GStreamer supported audio formats.

GNUPanel

Open Source Control Panel

GNUPanel is a completely free (GPL) replacement for proprietary web hosting automation software. GNUPanel is under development, focusing on translation efforts that permit the entire free software community to participate. Currently, GNUPanel is Debian-centric, however, a distro-agnostic approach is planned.
It is written mainly in PHP 5 and initially designed to run on 32 or 64 bits Debian GNU/linux.

Selenium - Open Source Software testing tool

Selenium is a opensource Framework testing tool mainly used for testing Web applications. It also provides a test domain specific language to write tests in a number of popular programming languages.

Step

With this interactive physics simulator, you place some objects on the screen, add some physical forces, and then see how they interact. It covers classical mechanics, particles, springs, gravitational and coulomb forces, collisions, molecular dynamics, and much more. (Note that in order to use Step on Windows, you'll have to download KDE for Windows.)