To set up a wiki all you need is an email address and the subject of your wiki. Set up an account and begin editing your wiki with pbwiki’s point and click editing tool to make pages and add media. Users can also go into existing wikis which they have access to in order to change or add new content. pbwiki supports RSS alerts, HTML support, built in search capability, 10MB free storage (which can be upgraded for premium users), 1-click wiki backup and free email support. To increase storage, further customize your controls or to have access to your traffic statistics users can upgrade to one of three premium packages.
An example of a collaborative wiki is the Rails 100 Wiki, which maintains a list of the top 100 sites using the Ruby on Rails platform.