reacTIVision is a computer vision framework for the fast and robust tracking of fiducial markers attached to physical objects, as well as for multi-touch finger tracking. It was mainly designed as a toolkit for the rapid development of table-based tangible user interfaces and interactive multi-touch surfaces such as the reacTable. Client application examples are available for various programming environments such as C++, Java, C#, Processing, PureData, Max/MSP, and Quartz Composer.
recorder.xhead is a voice recording application that can save sounds in .mp3, .mp4, .aif, .avi, .mov, or .wav format. Users can create a playlist of recorded sound, search it iTunes-style, and even export it to iTunes so that they can take voice memos on the road on an iPod. It plays audio streams, and comes with a bulk file conversion utility to convert between file formats.
While the OSS community converges to Git, with the Python bunch branching to Mercurial, the typical workplace is stuck with Subversion. The author's DVCS of choice is Fossil. These are all fine projects, with their own pros and cons, but what you usually want is just a tool to store your code tree snapshot in a safe place. They can all do that, but their language differs a tiny bit. repo brings them all down to the common root. It works by detecting which VCS are you using right now and calling that, applying necessary subcommand translation if needed.
retainCounter is an application that converts a simple [object release] into a NSLog(@"object retainCount: %i",[object retainCount]); [object release]; command. This is sometimes useful if developers wish to know the current count of an object before it is released, which makes it easier to detect memory leaks.