Online Users block (Part I) - How to be invisible on the Online Users block. A Moodle 1.9.x and 2.x solution

Learning Outcome: at the end of this post, you will know how to allow your Moodle 1.9.x and 2.x users to hide themselves on the Online Users block. This is Part I out of two parts. You can read Part II here.

Now I don't know about you, but I like, no, LOVE, the Online Users block by Andy J. Davis. It lends an air of Web 2.0 for Moodle. The feeling of a learning community that the block helps to foster is priceless. This block is useful for students and teachers to know who is online.

Figure 1: Online Users block.
A Moodle core block.