Currently re-reading the introductory sections on feedback loops in systems thinking and thoroughly enjoying it all again. Makes me want to build dynamic models for on of my current clients, or build a simulation tool.

Also, it has me thinking about the relationship between Systems Thinking and Goldratt's Theory of Constraints. How do they interact? Under which circumstances is each the more appropriate tool? Etc etc. Maybe there's some hobby maths to be done here...!