Free To Use. Pay To Play.
techcrunch.com
techcrunch.com
The functionality of Hacker News is very basic. It's the community that matters. Charing money would reduce the community, and somebody would quickly make an alternative site for people to jump to.
Of course using monetary barrier may not be the best way to achieve this. I don't know what would work better though.
But hackers are often the penniless idealist sort, and you need that sort to complement the actual businesspeople. As I said: college students are valuable for this site. And for something as generic as a social news site, money isn't worth it unless there's something very specific gained for the purchase, and there are already pay-for social news sites taking our valuable cash.
Alternatively, perhaps a "submit a paragraph explaining why you want an account" screen could also be used for people who won't/can't pay $1. Someone would have to weed through the entries, though (maybe make it open to votes, like stories).
I'm coming up short on ideas. Recommendation-only memebership?
Of course, that gives the IRC channel a lot of power. That might not be a good thing.
Yeah, that's it. That's what I'm looking for in an ideal community - relentless pursuit of that which works. This describes both the hackers and the business people.