You know what's not fun? Trying to send someone a direct message on Twitter only to find out that person no longer follows you.
Now, thanks to a new Mac OS X app called Bye Bye Birdie, you can find out which of your Twitter followers have defected. As it stands now, Twitter sends you a nice, heart-warming e-mail every time someone decides to follow you. But the service neglects to tell you when people stop following you. Bye Bye Birdie lives in your menu bar and displays a little message when you pick up or lose followers.
So if you care enough to know who found you too boring or annoying to keep following, download the app now for free here.