The name isn’t too thrilling, it’s slow to load, sometimes it only shows a black screen; but Surveillancesaver is now my second favorite screen saver (behind RandomWeb).
Watch more than 400 (don’t quote me) surveillance camera video feeds from around the world – updated in real-time. This is simply a Quartz Composer file (like the RSS feeds screen saver) that you install by dragging to Library: Screen Savers. There are NO options, NO preferences, NO tweaking (besides within Quartz Composer).
It takes a while to get up and running, especially the first time you try. But when it’s been active for a while it really starts moving, switching cameras about every 15-30 seconds. The time between cameras seems to vary, perhaps depending on the speed of the video feeds and availability of cameras.

More screen shots from Surveillancesaver on next page…
Notice the wide variety of cities and countries:







If you want a really cool, original, and constantly changing screen saver based on real life, as opposed to flying shapes or swimming fish, definitely download Surveillancesaver.