I'm reading Chris Turner's "Planet Simpson" which examines why The Simpsons is the greatest cultural and pop influence since sliced bread (which was the style at the time). One particular passage reminded me of Newgrounds' beginnings. While discussing how the 1970s-80s punk movement set the stage for the Simpsons he says:

"Some of the bands that made innovative music and some of the directors who re-invigorated movie-making and damn near all the pioneers of online content may not have looked or sounded particularly punk. But the overwhelming majority of them were inspired by and (to varying degrees) dedicated to its core values: strident, even nihilistic opposition to all authority; a preference for authenticity over virtuosity; a bias towards extreme subject matter; and, most importantly, a deep faith in the liberating power of the DIY (do-it-yourself) approach -- that is, the belief that anyone with a camera or guitar or computer, a strong will and a bright idea could create culture (and the bright idea was optional, actually)."

Even though NG has come a long way since the days of club a seal, I think the same core values and driving inspiration remain as underpinnings that guide the site and draw similar-thinking people to it, there's just a much larger community with a lot more talent throwing stuff in the pool these days.

Case in point:
http://www.newgrounds.com/portal/view/
490869