I know it's ancient tech, but there are so few parts of my computer where I can freely mix styled text, code, and data, and Mathematica is the only one where doing so feels remotely natural. I was inspired to post something by recent workflow breakthroughs in how I keep my lab notebook, where I slice-and-dice tabular data from experiment results in-between my paragraphs of stream-of-consciousness analysis. It's a lovely way to work. My journal entries build on one another in ways they never did before, because I can use code to put the best view(s) of the data right into the notebook.