What features of SharePoint do you use for Internal Communications?

I am debating writing a post about how SharePoint can be used as a tool to aid Internal Communications, but I wanted to do a bit of research first. Can you let me know how you get your messages / communications out to staff in your organization? Here are the options that come to mind (will update as you suggest them) :

• Announcement list
• Publishing / Wiki pages (for news items)
• Blog posts
• Discussions
• Surveys
• SharePoint Social  (e.g. activity feeds, tagging)
• Yammer
• SharePoint Alerts
• Community Sites

What about 3rd party tools? Do you utilise an SharePoint Add-ons to help with Internal Communications? Does anyone use any media such as video / podcasts etc?

UPDATE : I have written this up in How to use SharePoint for internal communications and also illustrated how DocRead can be used for Internal Communications.