Time Travel?

I was thinking about adding time travel into a star frontiers adventure.  There are so many ways to make it happen.  The players could find an abandoned, strange, device (You guessed it, a time machine), and accidentally travel to the past or future.  Or, the PGC could be unveiling their new time machines.  A criminal could steal one of them, and the players have to follow him/her in order to prevent the future being changed.  What do you think?  Is it too crazy?  What would the future be like for civilizations living in OUR future?