5. You can take a specific item entirely out of your Stream by clicking the small drop-down arrow next to it, then selecting "Mute this post." That'll also keep you from receiving any future notifications about the item.
6. On your own posts, that same drop-down arrow holds options to shut down comments and prevent people from resharing. The commands affect only the specific item you're viewing.
7. Sometimes leaving a comment on an active post can turn into a bouncing-screen challenge, thanks to the top-of-page activity always pressing your Stream downward. To solve this, click the drop-down arrow next to the post you're viewing and select "Link to this post." That'll open the post in a new tab; type your comment there, then close the tab when you're finished.
8. Google+ lets you stylize text within posts and comments. To italicize, sandwich your text with underscores _like this_; to make text bold, use asterisks *like this*; and to create a strikethrough effect, use dashes -like this-.
9. Make Google+ a little easier on the eyes with the Google+ Ultimate extension for Chrome. It separates posts into individual boxes with an offset background and forces the top status bar and left sidebar to stay in fixed positions while you scroll. Another good option is the similar Usability Boost extension; it gives a slightly different modified look to the site that some users may prefer.
10. Mention (or "tag") someone in a post or comment by typing "+" or "@" and then the person's name. Google+ is still a bit wonky at times about bringing up the right result; try typing the name slowly and enclosing it in quotation marks (e.g. +"Bob Sacamano") if you have trouble.
11. Improve the G+ reply mechanism immensely by grabbing the Replies and More Google+ Chrome extension. The extension puts links throughout G+ that let you reply to the author of any post or comment with a single click -- and without all the "+"-typing hassle.
12. To start a private conversation with a friend or multiple friends, just share an update like you normally would -- but be sure to remove "Public" and any other circles from the share box. Then, tag your friend or friends using the "+" syntax mentioned above. They'll receive notifications about the message, and you'll be able to have an ongoing dialogue in the comments for the post. If you want to be extra safe, you could also disable resharing using the process described in tip #6.