For smallish (one or a few files) library/API/snippet type stuff, I kind of like the style of putting the authors and changelog at the top of the file, along with brief documentation of using it and a statement of license terms. Bigger libraries will of course have separate ChangeLog and README files and such, but for one-file stuff, I often just end up copying the file into my own project, and it's nice when it's a self-contained file with the relevant info all in there.
How common that is might vary in different programming languages. It's quite common to share Javascript code by just swapping standalone .js files, and it's not uncommon in the Lisp world either.
How common that is might vary in different programming languages. It's quite common to share Javascript code by just swapping standalone .js files, and it's not uncommon in the Lisp world either.