Google Docs has learned a new trick: Voice Typing, the ability to recognize spoken words and commands. Now, Google Docs via Chrome, can edit and format documents by voice. To enable voice typing and editing, open a Google Doc. Click Tools on the nav bar, select "voice typing" and click the large microphone icon that pops up. Then, simply start talking. The keyboard commands to activate the microphone are Control + Shift + S (or Command + shit + S on a Mac).
For more details, check out Wired's article, "Now You Can Edit Google Docs by Speaking".
Here is a list of Google voice editing and formatting commands.