When coding, I use comments to help keep track of the tasks I still need to do. I enter these using this format:
// TODO: refactor this method
// TODO: non-empty textfields are allowed
Well, today I realized that Xcode's editor shows you these type of TODO: marks in the symbols list (the one where methods are listed, just below the toolbar), making it really easy to get an overall look at your "to be done" tasks. Note that you have to be careful when typing, since this feature is case sensitive, and very strict with the comment mark. It must be TODO:, with the colon at the end, a space, and then the to-do-task, as shown above. I'm not sure if this feature is present in older Xcode versions, as I'm using the last 3.1Beta.
// Something, TODO: more text
[robg adds: I haven't tested this one.]
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