Manage your follow/follower list with bulk follow/unfollow options
Twitter Karma is a simple application that lets you manage your follow list. It displays all the people you follow and lets you know if they are following you back. Options to Bulk Follow and Bulk Unfollow are provided to simplify the task!
As described on their site,
By default, the list contains all your friends and followers and is sorted by last update, showing those who most recently updated first. You can sort the list alphabetically either ascending or descending by Twitter ID. You can filter the list in several ways: only friends or only followers, all friends or all followers, and mutual friends.