SpaceTime is Free program for Mac OS X developed by P-Squared
Demonstrates the quick star land and skymap, preserving settings, embedding resources, etc. Written in legible Objective-C and Cocoa using Project Builder v2.1. If you reveal this software instructive as a programming example, or only wish to bolster the continued development of SpaceTime Screen Saver after OS X, I would greatly appreciate a Beerware donation of a dollar or two. Here's hoping you reveal SpaceTime to be a worthy addition to your Mac environs!
RandomWeb ScreenSaver is Free program for Mac OS X developed by Gabriel Handford
The RandomWeb screensaver randomly searches the internet for digital photos taken by the more fashionable commercial digital cameras and displays them. There are also modes to check by collocation (or dialogue) and by plot.