In a Harvard Business Review blog Peter Bregman writes about his experience of getting lost hiking in "Don't Get Distracted by Your Plan."
From the Hack the Market blog comes an interesting piece on constructing a pairs portfolio. Although it highlights the features of Stratbox, there are a lot of good conceptual tips that would work with any software.
The Deipnosophist blog always offers good material, some financial, some just plain fun. In the latter category I recommend Raymond Crowe's hand shadows video (April 13 post).