In its heydays, www.gigpad.com was a site that transformed the Indian rock music scene. It got the bands and their fans connected and worked as a phenomenally deep community. I've heard people complain that Gigpad was taking over their life, that they'd stagger out of bed late morning (after being online till 3 am) and log on right away, make a post on the forums and then spend the next half hour refreshing the page waiting for a reply. College kids going to rock shows would log on and find the band members talking music on the forums, and the same band members would greet them by their Gigpad nick at the next pub gig. Members going to a strange city would announce this and fellow Gigpadders in that city would give shelter, a bike, and a list of the pubs to visit, they would meet for extreme-cricket (don't ask!) on weekends.

This is not something unique to Gigpad, it's been done by a number of sites, some better than others, and there's something in the way they were run that the corporates trying to build online interactivity to build brand affinity could pay heed to.

The heart of the matter
Building a web community is not about the technology. There's so many powerful pieces of open source tools available (I've worked with Postnuke, Mambo and Joomla) that it's not terribly difficult for you to slap together a completely functional community site in very little time. The main trick we always tried to pull off, however, was to infuse the site with heart.

The ones creating the community need to believe in it so bad that it shows; that's when you attract the random visitor like a beacon. It's hard to give you a process to make this happen, but the best bet is if you yourself are the most rabid member of the community you're targeting. If not you, there needs to be someone in the team that truly believes in the site, and not just from a business standpoint.