Jessica Gruber wrote a cool article about how to create a menu in SharePoint using the SharePoint context menu and with data from an external data source. She came up with something cool:

"MSDN told us how to Customize the Shortcut Menu for List Items
Jim Duncan showed us how to move navigation elements (like Documents and Lists and Site Settings) to the Modify Shared Page menu
Ryan Rogers figured out how to delete context menu items
Mark Bower modified the original idea and gave us an example of adding context menu items with a hidden web part (no need for CustomJS or changes to ONET.XML)
But I wanted to take it just a bit further. I wanted a new menu altogether for my own type of data from an external source. And I wanted it to look just like a SharePoint context menu. So, standing on the shoulders of these giants, I came up with this.
Walk with me, if you will, through my process... "
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