Some people use wikis, like pbwiki, others use Ning, both help build online communities. So which cost-effective tools do you use to build your online communities? I personally have used Ning and though the community was very robust, some users found it hard to use. So which one do you use to build your online communities?

Based on what my clients approval, I have stuck with the basics (linkedin, twitter followers, facebook fans) and we have just started posting regular podcasts that our community members can subscribe to through a blog we run to target the clients potential user base. All have worked to the clients needs and provided solid results.