For a deep insight into this crucial activity, see Michael Jackson’s Software Requirements & Specifications, published by Addison-Wesley in 1995. (link)
Conceptual Blockbusting by James L. Adams (the third edition was published by Perseus in 1986) studies this kind of leap and is generally a pleasant prod towards more creative thinking (link)
Unlike the advanced methods, the aha! insights of algorithms don’t come only after extensive study; they’re available to any programmer willing to think seriously before, during and after coding (link)