Do you know that it is possible to bookmark individual email messages of Gmail just like you would bookmark any regular web page.
To experiment, open any Gmail thread in your browser and notice the address bar as it gets updated with a unique URL. That’s the permanent address of your email message and it will stay the same as long as you don’t delete the message from your Gmail mailbox.
Why Bookmark Gmail Messages
This could be a handy alternative to search in Gmail (for accessing important emails quickly) or may be useful in situations where you don’t want to create another tag in Gmail just to remember a couple of important email messages.
There aren’t any security issue because you can only access the email bookmarks if you are logged into your Google Apps or Gmail account.