Update Engine is a flexible Mac OS X framework that can help developers keep their products up-to-date. It can update nearly any type of software, including Cocoa apps, screen savers, and preference panes. It can even update kernel extensions, regular files, and root-owned applications. Update Engine can even update multiple products just as easily as it can update one.
JSCocoa uses parts of PyObjC.
The Touchless SDK enables developers to create multi-touch based applications using a webcam for input. Touch without touching.