If you listen to hip-hop, you know the boys from N.E.R.D.-it's just that you've been listening to their work under a much more recognized moniker, the Neptunes. While they've produced conventional, chart-topping hits under that name (and are currently regarded as having a musical Midas touch), N.E.R.D. is anything but conventional. It's the place where Chad Hugo, Pharrell Williams and Shay let loose their creative impulses and experiment. It's playful, weird, and as the name implies, a little nerdy at times. But it's also earned a reputation for pushing boundaries and trying things that aren't considered commercial enough for most hip-hop artists.That doesn't mean their music is less enjoyable, by any means. But it does mean that if you're the kind of person who likes to shake up the status quo, this might be your new favorite band. If anything, N.E.R.D. has proved they aren't content unless they're coming at their listeners with sounds they never expected to hear.The group's acronym stands for "No One Ever Really Dies." Their debut release, In Search Of... was famously recorded and released in Europe in 2001. But the band wasn't happy with it, and decided that the American release would need live instrumentation. They reworked the entire album, with the live sound provided courtesy of the funk-rock band Spymob. That album proved to be a calling card, and many critics came running, realizing the band had a unique take on hip-hop that wasn't being reflected in the mainstream world of flavor-of-the-month artists.Still, it wasn't until 2004's Fly or Die that the band really began to make a mark on the ears of listeners, "She Wants to Move" being the omnipresent hit that proved to be the fruit of their labors. In 2008, they came back with Seeing Sounds. The album's cover art let's you know you're in for something big-what could be bigger than the band confronting a massive, roaring gorilla? With the jazzy breakdown on "Everybody Nose," you can tell N.E.R.D. is attempting something a little artsy, a little different, but not inaccessible. If there's anything you can say to pin down their sound, it's definitely "fun."