Here is how to make your blink(1) blink the number of your unread mails every time you get a new one.

Credit to timb for the idea in this thread.

  1. Create a new AppleScript with this code

  2. Save the script in ~/Library/ApplicationScripts/com.apple.mail/

  3. Create a rule in Mail.app that will run the script every time you get a new mail.

  1. Let it blink!