What Tools Exist for User Published Content?

wbav asks: "Recently there's been a trend to user published content. A couple of examples of this trend include Wikis, Podcasting, Blogs, and the resulting RSS Feeds. Last night I was asked if any other similar technologies exist. As I did not have a good response, that is my question to the slashdot community. Are there any other similar technologies which deal with user publishing that I have not mentioned?"