If you have a Domino Mail server and Domino Web Access Templates for users, it could be interesting to present to the user an indicator of unread emails.
This code works for the moment only on IE.
Something as below :

To do that easily, I have used the XML representation of DWA.
You can obtain that with that url :
http://servername/mail/userdb.nsf/iNotes/Proxy/?OpenDocument&Form=s_ReadViewEntries&PresetFields=FolderName;($Inbox)
In this XML file, you have the information if an email is unread.
As shown below :

After that, you just need to parse that file and count the number of unread emails. To do that, you use a small JavaScript piece of code.

If you also want to add a link to the Mail Page, you can add the following lines. These lines generate a URL to the page “ibm.portal.Mail”, and I also use NLS bundle to add some text before and after the number of unread emails.

You can find all the source code, here.