Here's a question for you
The new film ‘Avatar’ tells the story of an ex-Marine who finds himself in a war-zone on an alien planet. Now an Avatar – a human mind in an alien body – the ex-Marine must fight for the survival of both himself and the planet’s inhabitants.
The fantasy question is:
If you could transfer your mind into another body when that body becomes useless (or regenerate the same body - a bit like Doctor Who) and, in effect become immortal, would that appeal to you? Could you cope with living for thousands of years? What if you became imprisoned somewhere or trapped underground and couldn't escape, would you go mad? Imagine the power, wealth, knowledge and skills you could acquire over that time - what would you do with them?
Avatars, New Bodies et al.
If you want a really good read - (sci fi with swapping bodies left right and centre), I can highly recommend Altered Carbon by Richard K. Morgan - and virtually everything else he's written - modern, with an edge and written by someone who writes as if they understand digital technology - spot on.
Synopsis of Altered Carbon from his website Richard (K) Morgan, science fiction author
In the 26th century mankind has spread through the galaxy, taking its religions and racial divisions out into the cold arena of space. While tensions exist and small dirty wars flare up every now and then, the UN Protectorate maintains an iron grasp on the new worlds, aided by its very own elite shock-troops; the Envoy Corps.
Meanwhile, what religion cannot guarantee technology has already delivered; when your consciousness can be stored in a cortical stack and routinely downloaded into a new body even death has become little more than an inconvenience. As long as you can afford a new body...