A little more info, if you please.
What kind of 'one large file'? A full backup, perhaps? Splitting it into multiple smaller files is possible using DAR (slices in DAR-speak).
Your great novel? There are ways to use word processers and type-setting software (LyX) to do each chapter individually, then combine them into a book.
As Jhonny 5 would say: 'Need input', or I can't be of much help.