What is OnyakTech Auto Log-In?
OnyakTech's Auto Log-In DotNetNuke Module allows your visitors to instantly log-in to your web site using an account you specify.  Simplifying processes for your visitors to get them to the heart of your web site content quickly.  There are many uses for OnyakTech's Auto Log-In, one of them being the ability to quickly grant your visitors access to a demonstration of products and/or services you offer by removing the unnecessary step of walking them through the process of logging into your web site.  It's EASY TO USE.  See it in action on www.SigmaProDraconis.com

Features:

• Customize the text of the link visitors click to instantly log-in
• Localized
• Account validation
• Easy to install and setup
• Does not alter the core of DotNetNuke
• Compatible with DotNetNuke 3.x and 4.x
• Supported on .Net 1.x and 2.x
• Compatible on all major browsers including Internet Explorer and FireFox

For more information and to download this module, go to www.OnyakTech.com

No, it won't provide the functionality your looking for.  Auto Log-In is a java script post back to the server, it won't work if the link is copied to an email. 

However, the functionality can be added to the module.  With a few changes, a link can be provided that you can use in emails.  But this will log-in the user in using an account you specify.  If you should need to log the user in as themselves, it may be better to extend the time-out period of the authentication cookie in the web.config and then simply provide a link to the secured pages in your email.  At that point, DNN will handle the authentication and they will instantly log-in since the authentication cookie still exists.