Inside Knowledge talks about blogs and wikis and their tendency to enter organizations at the bottom-up level:

If you think that your organisation does not use blogs or wikis, then you may need to think again. Just as instant messaging appeared informally a few years ago, blogs and wikis are appearing as skunkworks projects across a large number of organisations. A blog is a good method of distributing information but its value really ends there. A wiki, however, provides facilities for a much more sophisticated exchange of information, since a wiki is a website where readers are able to contribute content and edit existing content.