One thing missing from many peoples pages are Alternate Earth settings, something that Rift's provides and endless possibility for.  After recieving my official 250th nasty e-mail that my Rifts site is not "By the Book" I set out and created worlds that will drive these rules lawyers to distraction, and ruin any players that rely on what the books say, not thier skills....
  At least, that was my intention.  This quickly grew out of hand, and my party had a lot of fun playtesting these worlds, well, until they hit "Cyborg Paradise", a world where the Mechaniods are winning the Mechaniod Invasion.  The Magic Using CS and the CS Atlantis were fun for them, as were the 12 Baronies, and the Paradise Lost (Where most of the world governments and tech survived, and the date was 2349.  Quickly turned into a great time, playtesting and transcribing these onto the computer.  I've seen enough homebrewed worlds to know that I'm possibly on to something here.  Thinking about the possible consequences of small actions, or worlds where the PC's lost in hingepin battles.
  Here are the worlds, some of them have not been transcribed yet, but bear with me, they will.

Livin' in a Cyborg Paradise-The Mechaniods are winning the Mechaniod War
No Holds Barred-A Magic Using and Controlling CS, featuring CS Lazlo, CS Tolkeen, and CS New Lazlo
Anarchy in the USA-Where the Federation of Magic beat the CS, completely eliminating them
Splugorth No More-CS Atlantis, Federation of Magic, Chi-Town under siege, and more!
Paradise Lost-CNN Special Report, a force of over a dozen Brodkil Demons have attacked the New York Subway.
Twilight Hours-Where the Rifts were created by a high-tech Brodkil race invading Earth....
The Twelve Baronies-Twelve Supercities, the only true bastions on mankind in North America
Better to Rule In Hell-An Alternate Germany where the NGR was crushed in 63 PA and was forced to North Africa
The Dark Age of Man-My campaign, where there was much more tech before the fall, and more old stockpiles.
Honey!  The Freezer's Busted-Where the PC's get out of cryostasis around -75 PA.