WIRED:Internet marketeers are no longer so deluded as to believe that they can simply create an online forum and expect to generate a community of brand zombies, writes DANNY O'BRIEN

I REMEMBER, back in the charmingly naive early days of the business web, when one of the cola companies set up a forum as part of its main website.

The advertising executives were tremendously excited: here for the first time was a chance to find out what their customers really thought of their soft drink! Customers would chat online about all aspects of the brand, sharing their excitement with new drinkers and increasing their self-identification with the brand with every posting.

Anyone who has actually used or stumbled upon an online forum could guess what happened. The cola forum, rather than becoming a one-stop internet shop for all your soft-drink discussion needs, instead became a brand cesspit.

It was popular, certainly, but its users were haphazard visitors to the website, who initially just used it like a graffiti-inviting wall.

Later a community of sorts grew up, but it was made up of a few hundred kids who had randomly decided to make this website their hangout for making flirty, occasionally abusive, small talk. If the host's product was mentioned at all, it was in the form of a running joke about how awful it was: an attempt by the forum denizens to bait the moderators into deleting their posts.

This, in fact, rarely happened, because the onslaught of postings was so great that the site managers could rarely keep up, and had no tools to search or mass-delete items.

We're somewhat wiser now: while internet marketeers still talk of the importance of community in working online, they're no longer so deluded as to believe they can throw up some comment forms and expect to generate an online audience of brand zombies eager to do their marketing bidding. Most brand "communities" are heavily channelled, cautiously executed online Potemkin villages.

Companies such as Satisfaction are now paid by major brands to take away the headache of managing their online communities; the internet is seen as a place where customers need to be listened to and reassured quickly, before their complaints turn into a PR nightmare.

But what if you really do want a community attached to your product? What if your product depends on that community being happy and productive and feeling loved?

That's the challenge being faced by hundreds of companies that have tied their flag to the "social software" mast.

When Twitter, the popular (and well-funded) chat site, went down earlier this week, its users went from being its best advocates to its worst critics within days.

I've been thinking about communities a lot this week, because I have been a judge for the digital communities category of the prestigious Austrian internet art award, the Prix Ars Electronica.

For an art prize, a significant number of dotcom "community" startups entered - which just goes to show the accuracy of my fellow judge Isaac Mao's comment that building an online community is an art.

I wouldn't presume to prescribe a list of dos and don'ts for anyone wanting to blend a community with their upcoming business, but I would definitely recommend spending a lot of time hanging out in successful online communities, commercial or not, and watching them to work out how they tick.

First, unlike a traditional business, it makes sense to grow a community slowly so that you can preserve some sense of social cohesion. A small group polices itself; a large group that emerges suddenly has no history, and quickly descends into civil war.

One of my favourite communal websites, MetaFilter, imposed controls on its growth by charging a token amount to new users once it had grown beyond a certain size.

If you don't want cost (or the hassle of paying online) to be the limiting factor, consider taking a leaf out of Google Mail's book: grant your existing users a limited handful of exclusive invites to send to their friends.

That way, you can not only control growth, but you can create a chain of responsibility, where users can be trusted not to ruin the community by inviting in louts.

Moderation is no longer a dirty word on forums. Boing Boing, one of the largest blogs online, originally had an online forum that descended into unpleasant infights and name calling.

Several years after that was closed down, it returned, with a strictly moderated discussion.

To avoid some of the problems that can be created by a heavy-handed editorial policy, Boing Boing's moderators instigated some ingenious new techniques; one was "disemvowelling" - removing the vowels from an intemperate post, to make reading harder without censoring outright.

But Boing Boing, MetaFilter and hundreds of other forums work best when they extend power, not concentrate it.

All of these forums allow the community to self-police - in other words, you can flag disrespectful or offensive posts for the moderators to view, and the moderators themselves are frequently drawn from the community.

As long as you're willing to invest time and resources, and you don't expect your community to talk constantly about how great your cola drink is, you can have a safe online community and a great business product too.