Business Insider: Elon Musk's aspirations for Twitter include a mysterious new product named "X," according to his investor presentation obtained by The New York Times.

Product "X" would launch in 2023 and bring in 9 million users within the first year, the pitch deck estimates. Musk projects 104 million users would subscribe to the product by 2028, per the Times report.

It's one of several ideas outlined in the billionaire's grand plan to quintuple Twitter's revenue and quadruple the size of its user base, despite his previous claims that he doesn't care about the economics of buying Twitter "at all."

While no other details were revealed about the secretive feature, the Tesla CEO has mentioned a handful of changes he plans to make to the social media app if his $44 billion purchase is approved. Among them are an edit button and an ad-free version of Twitter.

The pitch deck also described a "payments business" that Musk estimates would produce $15 million in revenue by 2023, the Times reports. Both Musk and Twitter co-founder Jack Dorsey have experience in digital payments — Musk is one of the original co-founders of PayPal and Dorsey is the CEO of Square (now called Block).

Musk did not respond to Insider's request for comment on product "X" and what it might entail. In an April press release, Musk said he wants to improve Twitter by "enhancing the product with new features, making the algorithms open source to increase trust, defeating the spam bots, and authenticating all humans."

Twitter's board unanimously accepted Musk's buyout at $54.20 per share on April 25. The deal is is expected to close in 2022, "subject to the approval of Twitter stockholders, the receipt of applicable regulatory approvals, and the satisfaction of other customary closing conditions," Twitter said in a statement.