It doesn't take long to lose track of who's following you and even who you're following. These tools provide insight into your network.
If you're wondering whether an individual follows you, DoesFollow (http://doesfollow.com) will let you check easily.
To see all your followees, fans (i.e., followers) and friends (mutual followers), try FriendOrFollow (http://friendorfollow.com).
If you want to find out what your followers say they're interested in, Twittersheep (http://twittersheep.com) will create a tag cloud from the bios of your network. Here you can see the cloud for social media marketing expert Chris Brogan (@chrisbrogan).