Particularly time travel, and the likes.

Anyone?

Michio Kaku's Physics of the impossible was quite interesting. I believe it covers time travel.

Bill Bryson - A short history of nearly everything.

Basically, it delves into pretty much every aspect of science, and explains that field and it's history in laymans terms, then explains how it relates to surrounding fields, and tells you the key historical and current players in that field.

Covers things like the big bang theory, gravity, light, molecules, atoms, electrons, quantum physics, radiocarbon dating, paleontology, volcanology, chemistry, string theory, you name it. I'm three quarters the way through it right now.

Black Holes, Wormholes and Time Machines - Jim Al-Khalili

Got some really interesting stuff that you'd probably like about creating wormholes, exotic matter, Tippler time machines etc...

Thanks for the suggestions, my girlfriend has lots of Bill Bryson books so I'll have a look for that one, and I've ordered Physics of the Impossible :D

Thanks again.

World's Greatest Popular Science Books:
http://cosmicvariance.com/2008/08/29/the-thousand-best-popular-science-books/