Nomi Nomi no Mi

The Nomi Nomi no Mi is a Paramecia-type Devil Fruit that allows the user's brain to expand indefinitely with new knowledge, making the user a Brains Human (脳ミソ人間). It was eaten by Vegapunk.

Etymology

 * "Nomi" is derived from nōmiso (脳ミソ) which means "brains" or "brain tissue" in Japanese.

Strengths and Weaknesses
The major strength of this fruit is that it allows the user to store an indefinite amount of information inside their brain, allowing them to remember everything they have ever learned. However, the user's brain and head must expand accordingly to fit all the knowledge. This can cause the user some issues, as having an unnaturally large head can become very inconvenient. Aside from that, the user suffers the standard Devil Fruit weaknesses.

Usage
Vegapunk has used this ability to memorize an enormous amount of knowledge, which together with his natural genius intellect has made him the smartest man in the world.