The Gutenberg white paper
Human Made released a white paper covering everything about Gutenberg and the changes it will bring into WordPress 5.0.
The white paper is excellent, but this is also an excellent sales tool. You enter your email address and get subscribed to their newsletter to download it, and then the white paper itself is an excellent guide to Gutenberg, laid out in a way that would make sense to an in-house technical director or decision maker — not just developers.
Additionally, there are subtle cues to hint about Human Made throughout, ending with information for their sales team. I realize this may be straightforward sounding, but I haven’t seen a ton of this sort of thing in our industry, and I just found it particularly effective. I could imagine product and service agencies alike using similar strategies to get greater reach with customers, all the while educating them.