I believe the only reliable way to make reusable code is to reuse it as you write it. If your team is working on several projects at the same time which have so

I believe the only reliable way to make reusable code is to reuse it as you write it. If your team is working on several projects at the same time which have some overlap, then by all means if something could be useful for three or more projects, get together with everyone else and strive to write something you can all use. It will be reused immediately, so that's clearly reusable. But don't try to write something you'll reuse in the future; you don't have enough information to know if you are building the right thing, and you won't know if you did until you try to reuse it.