Sometimes I take a look at other people's code just to see how they implemented something, even if I've already implemented that something in my own code.
Diving into a huge codebase is daunting, but I love reading snippets or small scripts written by other people.
I find reading other code is a great way to learn. I'm working through both Quantlib and GNU Scientific Library to learn numerical methods that can be used in finance. Theory is one thing, but when you see an actual implementation of it, then it becomes much more clear.
Sometimes I take a look at other people's code just to see how they implemented something, even if I've already implemented that something in my own code.
Diving into a huge codebase is daunting, but I love reading snippets or small scripts written by other people.