Wall Street lore holds that “junk bond” king Michael Milken once blamed the tumultuous changes that roiled American finance in the 1980s on VisiCalc, the pioneering spreadsheet software. This article takes Milken's quip as a prompt to explore the practical and cultural place of computing in 1980s finance. It reveals that PCs, especially spreadsheets, augmented the capacities of 1980s financiers in three ways—surveillance, valuation, and imagination—each crucial to Milken's “machine.” Yet this article also exposes another side to Milken's success, grounded not in computation but charisma. Milken's power lay both in innovative command over novel technicalities and a simultaneous sense that he possessed a suprarational vision transcending the technical. Milken's spreadsheets help us to reconsider a central debate in the social studies of finance about the “ghost in the financial machine” and to examine the co-construction of “killer apps” and “killer applicants” in the early history of personal computing.