freeglut is intended to be a 100% plug-compatible clone, and is released under the Xfree license. The GLUT (OpenGL Utility Toolkit) is a widely used library for doing window control, keyboard, and mouse input, and other basic functions for OpenGL programs. However, GLUT is not OpenSourced - although it's source code is available under a somewhat ill-defined set of restrictions. Hence, 'freeglut'.
Java Supplements is a free library of utility classes which extends and enhances the functionality of the classes provided by the normal Java API. It provides robust and reliable code for doing many of the tasks which Java developers commonly find themselves writing code for again and again, such as catching InterruptedExceptions on Thread.sleep() calls or reading files into a byte array.
libview is VMware's Incredibly Exciting Widgets, a collection of GTK+ widgets used within VMware products. These widgets are the same ones used in VMware Workstation 5.0 and higher, and were considered useful enough to open source so that others could use them in their own projects. These widgets are actively developed and maintained.