The Neptunes—Pharrell Williams and Chad Hugo—were two of the world's most in-demand producers by the start of the 21st century. But they were also fiercely independent in their own way, as their side-project N.E.R.D proved. With third member Shay Haley rounding out the crew, their 2002 debut, In Search Of..., revealed them to be forward-thinking eclectics with aspirations towards future funk, power pop, slow-jam balladry and all points in between, with ensuing records like Fly or Die, Seeing Sounds and Nothing following deeper into pop-laboratory experimentation. While their string of singles could've easily been used to provide potential chart-topping fodder for rap and pop superstars, keeping those beats for their own use made for some of the aughts' most eccentric cult hits. Equal parts irreverent and sincere, grimy and gleaming, lowbrow and high-concept, N.E.R.D's weirdo auteurism gave the Neptunes free rein to be whatever they felt like being.