This is a simple tutorial that will allow you to make a custom google toolabar button for your pligg based website.
It will retrieve your popular stories each hour. The stories are available in a drop down list next to the button.


Create a file on your pligg root called googlebutton.xml

Edit the following code to match your own pligg site details.

Code:
<custombuttons xmlns="http://toolbar.google.com/custombuttons/">
  <button>
    <title>Pligg Demo</title>
    <description>http://www.pligg.com/demo</description>
    <search charset="ISO-8859-1">http://pligg.com/demo/search.php?search={query}</search>
    <site>http://pligg.com/</site>
    <icon>
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    </icon>
<feed refresh-interval="3800">http://pligg.com/demo/rss.php</feed>
  <update/></button>
</custombuttons>
The icon requires base64 encoding and can be changed by passing your own icon through
Base64 Online - base64 decode and encode and replacing it with the code in between <icon> and </icon> above.

Now by linking to yoursite/googlebutton.xml it will initiate the installation.