While Google Apps are a productivity suite, I more so think of them as a collaboration suite. The new Google Drive now makes it even easier to connect and collaborate. Select a file in Google Drive and click on the link icon in the toolbar. This gives you the link to the document to share.
The URL is already highlighted, simply hold down the control key and press C to copy the link to the clipboard.
You can now paste the link using Control V into a hangout chat, text message, email, Google Plus, or any other way that you connect with collaborators.