A running list of my own: http://www.gwern.net/Notes#fermi-calculations (And there’s a number of them floating around predictionbook.com; Fermi-style loose reasoning is great for constraining predictions.)
A running list of my own: http://www.gwern.net/Notes#fermi-calculations (And there’s a number of them floating around predictionbook.com; Fermi-style loose reasoning is great for constraining predictions.)