Development toolkit for Web Services and XML data bindings for C & C++
3D Engine c++
Free 32/64/16-bit multi-platform Pascal and Object Pascal compiler
Java UI Framework for Desktop/iOS/Android
JavaScript framework to build game engines, games, emulators and apps
A cross-platform interpreter for many point-and-click adventure games
Qt wrapper library for the ZXing decoding library.
Apache Cordova framework for showing websites as mobile apps