Actually a book that ended up changing my life:
Kaczynski, Mischaikow, Mrozek: Computational Homology

I read it while working on my master's thesis in computational homological algebra, in order to see what they had to say about efficient implementations of simplicial homology.

After reading it, I first realized that algebraic topology has applications far outside what I had seen thus far - and now, a doctorate later, I'm active in the field of Applied Algebraic Topology and Topological Data Analysis.

I'm not certain I'd peg it for *great writing* as such, but the criteria above *did* state "changed my life".