CityLizard++ is a set of general header-only C++ libraries.,

Develop a scalable cross-platform user interface for managing one or more BOINC clients.

IUP is a small multiplatform toolkit for C and Lua.
The Unix backends are Motif and Gtk+. This adds a Qt backend.

An OpenGL toolkit,

QMira is a cross platform software ( mainly linux, windows ) which aims is to send images between two computers using the RTP/RTPC protocol.
It's a kind of videoconference software, but instead of using mpeg as movie format, still jpeg images are send accross the network according to the RFC 2435 at a given framerate....

Framework for development of mail software, based on Qt. It is used on Nokia MeeGo N9.

The Bubbling Load Monitor (or "Bubblemon" for short) is a system load monitor for the GNOME panel. It looks like a vial containing water. The water level indicates how much (electronic) memory is in use. The color of the liquid indicates how much swap space is used. The amount of bubbles reflects the system CPU load. A message in a bottle indicates there is unread mail. A reed-like graph shows IO load....

Open Source Biometric Recognition and Evaluation,

An opensource song notation typesetting environment for editing and publishing Carnatic music books in Indian languages by Gopalakrishna. Supports Phonetic Translation of notation & lyrics and uses CFugue Runtime to automatically generate MIDI song files from the music notation....

YB.ORM tool is developed to simplify writing C++ code dealing with SQL databases. The approach used is known as the Object-Relational Mapping (ORM). The goal is to provide a convenient interface like SQLAlchemy (Python) or Hibernate (Java). There are ports to Linux and Windows (MinGW, VC). SQL dialects supported: MySQL, Postgres, Oracle, Firebird. You can build and use YB.ORM with your favorite toolkit: Boost, Qt4, or wxWidgets....