Inqlude provides a comprehensive listing of all existing libraries for developers of applications using the Qt toolkit. Inqlude is run by the community and open for contributions.
Building blocks for Qt applications
Qtilities is a set of well documented and mature Qt C++ libraries which provides building blocks for Qt applications, allowing rapid application development. The project consists of different modules which provide features which are common to a wide range of Qt applications, with the main goal of making common things easier to do.