Google Alerts is a free service in which you tell Google which words or phrases or names are important to you.  Then, every single time those words appear anywhere on the Web, you are instantly alerted. 

How do you use this service to make money?

YOUR OWN NAME

Enter your own name -- hopefully you have a rather unique name so that the hits are relevant -- and Google will alert you by email every time your own name appears on the Web.  Here's what I do.  As soon as I see that my name has appeared, I instantly click on that link and it is almost always someone's blog.  I read the blog entry and find something interesting that the person has said about me (or maybe that person has reproduced one of my published articles).  Then, I submit a reply to that blog post thanking the blog author for saying such nice things about me.  They are typically shocked because they may have written their blog post just minutes before and I am already thanking them.  I also offer some give-away in my reply (like a free download) for which they will have to get squeezed.  In this way, I find a whole new set of potential buyers.  And, the blog author is usually so complimented that the person that they just wrote about has acknowledged them that they hopefully will write about you again.

YOUR COMPANY NAME OR SLOGAN

This works exactly the same way as with entering your name.  Be creative.  Enter as many different words or phrases or names as you wish.   It's lots of fun.  And, I guarantee you that sooner or later - probably sooner - you will be startled at what you learn.  You will be amazed at who is writing about you.