Less of a tool and more a guiding principle, I was reminded recently of the value of Parkinson’s Law. The basic rule is that work expands to fill the allotted time e.g. give 12 hours to do a 6 hour task and it will take 12 hours! Being time savvy though, I find I get the best value by allocating short periods of time. This creates a sort of neural tension. Like the sand falling through the central pinch of the hourglass, the brain becomes more focused, so more gets done in less time.