How would you start such a mailing list from scratch without a blog? Say one (or more) interesting thing publicly, promise more interesting things in return fo

How would you start such a mailing list from scratch without a blog? Say one (or more) interesting thing publicly, promise more interesting things in return for signing up for the mailing list. It's certainly easier to bolt things onto a platform than to build a platform from scratch, but everybody starts with +/- nothing, so having nothing should not deter you from starting that.