Depends exactly what you mean by "got an idea ... from a sci-fi book". If you mean "copied directly from a sci-fi book", you shouldn't be able to patent it -- the USPTO has accepted science fiction as prior art in the past. (Naturally, it's only prior art if it describes the <i>method</i> -- Star Trek transporters aren't prior art for anything, because the mechanisms behind how they work were never specified.)<p>The most famous example of fiction being cited as prior art is probably the method of raising a sunken ship by filling it with ping pong balls, where a 1949 Donald Duck cartoon was cited.