YouTube, from Chrome’s omnibox?
Chrome automatically saves a list of the search engines you come across while browsing. So, if you visit http://www.youtube.com, Chrome will add the YouTube search engine to your list of search engines. And, from then on, you’ll be able to search YouTube directly from the omnibox by typing http://www.youtube.com, pressing space, and adding your search terms. If you want to view, update, or modify your search engines, follow the path Chrome Menu > Settings >Manage search engines.
ProTip: On the Manage search engines page you can also define keywords for websites to save yourself some typing; for instance, typing “yt” could be a shortcut for http://www.youtube.com.