A new biography of Fisher Black notes that he did most of his work in the old outlining program, ThinkTank. Fisher is the "Black" in "Black-Scholes", the options pricing model used extensively in modern finance.
I loved that software too! It was available on the early Macintosh and the publisher, if I remember, ultimately phased it out in favor of another package called "More". Both titles were driven out of the market by the terrible outlining features of Microsoft Word. Outline processors were such a great idea; I wish somebody would resurrect it.