I'm excited to share this series with you, called "101 Blogging Tips". In the series there will be 101 blogging tips that you can begin applying to your blog today! Don't wait, get started now!
Tip #80: Communicate with Live Chat
One of the better ones I've come across is Olark. For most of use, the $15/month Bronze, 1 operator plan would be sufficient and affordable. Add something like this to your site!
Here is the installation instructions and the WordPress integration guide (self-hosted only as the WordPress.com free sites do not support JavaScript).
In Blogger, you need to go to Template, then Edit HTML and paste the code from your Olark dashboard above the </body> statement.
In TypePad, if not using Advanced Templates where you would have access to the </body> tag, you can simply add a Notes TypeList or Embed Own HTML Code in the FOOTER area.
NOTE: You do NOT want to install this type of feature if you're never going to be around to chat with your readers/visitors. Of course, you can always set it to "not online now" but you don't want that to be the norm!