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The BEST Add-Ons

The Best Add-Ons List
Add-On Name Overview Notes
XLMiner Analysis ToolPak Statistical analysis in Google Sheets, with functions matching the Analysis ToolPak in desktop Excel. Requires setting up access with a Google account.
SSH Agent for Google Chrome Provides an SSH Agent implementation for Chrome's Secure Shell extension. Also known by Secure Shell App
Text Editor Simple text editor. Great way of stripping out formatting code just to be left with text.
Auto-LaTeX Create LaTex in Google Documents More information can be found here.
Markdown Preview Plus View markdown (.md) files More information can be found here.