2011-12-13 // How to subscribe to a Google Group with a custom email address
The interface of Google Groups implies that you can only subscribe with a Google Account and its email address. But even Google makes it harder than it should be, it is possible to use any other valid email address to subscribe. You just have to call the subscription page manually by editing a URL:
http://groups.google.com/group/name-of-the-group/boxsubscribe?email=your-url-encoded-email-address
Just substitute the following:
name-of-the-group
→ the group you want to subscribe toyour-url-encoded-email-address
→ your url-encoded email address