Miramath is an Open Source project inspired by the MathCad mathematical application. The main user interface consists of a page into which mathematical expressions can be entered or edited and then evaluated. It features a Wysiwyg equation editor, automatic evaluation of equations, integrated plotting, symbolic algebra using Sympy, and numerical computations using Scipy.
QSapecNG (Symbolic Analysis Program for Electric Circuits (New Generation)) is a Qt-based program for symbolic analysis of linear analog circuits. It consists of two independent parts, the SapecNG framework engine and the QSapecNG GUI. It was based on SapWin. Users can draw, solve, analyse, and manage analog circuits.
4K Video Downloader is a video and audio downloader for YouTube, Vimeo, Facebook, Dailymotion, Metacafe, and other video-sharing services. It features video quality up to 4k resolution, FLV, MP4, and MKV support, extraction of audio to the MP3 format, and a "Smart Mode" for fast downloads.
The libQtSerialization library is a Qt extension that makes it easy to serialize your data in a forward and backward compatible way. The library is composed of QWriter and QReader. The writer is straightforward - all you have to do is call a writeTag() function and the data is serialized. The reader is a little more complex as it supports special cases, such as sub-classes (so you can save a tree of classes) and arrays of classes (your tree may be composed of multiple instances of a given object).