Different Universes....

From The Fannish Friday Five: Name the five best uses of parallel universes. Is a parallel universe the same as an alternate universe? I don't usually like the theme, but sometimes... sometimes it's terrific.

1. The "Mirror, Mirror" episode of Star Trek the original series, followed by two visits to the same universe in Star Trek: Deep Space Nine.
   
2. Doctor Who episode 4x11, "Turn Left".
   
3. The Uncanny X-Men #141, "Days of Future Past".
   
4. Superman: Whatever Happened to the Man of Tomorrow? by Alan Moore.
   
5. All the fanfic, all the slash, written about all my favourite fandoms. Each story creates a parallel universe (and/or an alternate universe) all its own.