http://trolltech.com/developer/qt-creator/qt-creator#qt-creator-open-source
Qt® Creator is a new, lightweight, cross-platform integrated development environment (IDE) designed to make development with the Qt application framework even faster and easier.
Tailored specifically to the needs of Qt developers creating cross-platform applications Focuses on features that boost developer productivity without getting in their way Helps new Qt developers get up and running faster Open and extendable; integrates familiar tools and file formats
The final release of Qt Creator is planned for early 2009.
Доступны сборки под linux 32 и 64, mac os, windows и исходный код в git.