A few months ago I came across a freeware 3D screensaver called 'A Walk in the Countryside' from TLA Data Systems. See http://tla-data.co.uk/downfree.htm
It's a simple click install and it does what the title says. Every time the screensaver starts you begin at a random location and travel through the scenery. It had occured to me that the landscape of Oblivion itself would make a great screensaver. Either as a seperate independant screensaver program or purhaps, a mod that activates a random travel location screensaver of the installed game.
P.S. You will understand better if you see the TLA screensaver.