Catfood Follower 1.40 is now available for download.

Follower is now integrated with Klout, a service that measures the influence of Twitter users with a score ranging from 0-100. You can choose to only follow people above a certain Klout score, or to remove followers below a certain Klout score.

I’ve also added support for using Twitter Lists as unfollow exceptions. This is much easier than remembering to run Follower and add an exception for each account that you want to always follow. Just add people to a private ‘don’t unfollow’ list and then check this off in Follower Settings. You can add as many lists as you like as unfollow exceptions.
1.40 also includes a big performance boost. Under the covers accounts are now processed using Twitter APIs that return up to 5,000 friends or followers at a time. Before 1.40 Follower would process around 200 accounts per API call. This change means that Follower runs faster and is less likely to hit Twitter call limits.
If you already use Follower upgrade today. If not, and you’re looking for a way to manage your Twitter account check it out and read Getting the most out of Catfood Follower.
I’m close to releasing a new version of Catfood Follower.
The update has some cool new features including Klout integration and a switch to bulk twitter APIs that allow the follow engine to run much more quickly. I’ve also mopped up several bugs and generally tidied up the interface.
Download Catfood Follower 1.40 Beta and leave a comment below if you have any problems, questions or suggestions. Thanks.
(Updated 2011-10-22: 1.40.0136, improves Klout integration so that processing an account does not fail because of temporary Klout failures.
Catfood Follower has been failing with a (401) Unauthorized error message since Thursday night.
Twitter has suspended API access for follower because they object to a blog post on how to use it. I’m working with Twitter to try and understand their concern and hopefully Follower will be authorized again soon. I’ll update this post as soon as I have more news.
(Updated 2010-11-18 17:00 PST: Follower is working again. Let me know if you run into any problems.)
Catfood Follower 1.30 introduced some changes to removing traitors: followers who have stopped following you back. This post will help you understand how to get the best results from the new Follower.

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I've just released Catfood Follower 1.20, a tool for automatically following people who follow you on Twitter.
Download Catfood FollowerThe new version fixes a bug which caused updates to fail when processing the new location information in tweets. It also supports per-run limits on follows and removals and includes better error logging.
I've just released an update to Catfood Follower. Follower is a tool for Twitter users that allows you to find and remove friends who have stopped following you. It also allows you to automatically follow anyone who starts following you (but does not send automatic DMs).
Download Catfood Follower
Follower 1.10 is much better at handling Twitter API limits. Rather than failing to update it will wait until the current limits expire and then keep going. It will work much better for people with many accounts, friends, or followers. 1.10 also uses the new cursor method for paging through lists which is more reliable.
There's also a new window that shows progress when automatically processing rules:

This is now the default when running Follower.exe with no command line argument. If you prefer the old behavior run Follower.exe /silent and the update will run without any notification.
It's also now possible to cancel Follower, either from the test window or when running automatically (as long as you're not using the /silent switch).
I've just posted an update to the Twitter Public Timeline Screensaver - by popular request you can now add your account (actually as many accounts as you like) to display on the screensaver as well as the public timeline. It's also now possible to change the colors for the screensaver including setting a custom color scheme for tweets from each account.
Catfood Folower has also been updated recently. This is a tool to automatically follow and unfollow people on Twitter based on rules that you set. It's useful for company accounts where you want to follow everyone who follows you, and also for finding and removing friends that no longer follow you back.
Catfood Follower is a desktop Twitter tool for following new friends that follow you and removing friends that don't follow you back. Follower supports Windows XP, Vista and 7.
Download Catfood Follower (Current version: 1.40.0147)
After installing please read Getting the most out of Catfood Follower.

Why auto-follow?
I have multiple twitter accounts. My personal account (@abfo) doesn't auto-follow. If you look interesting and not obviously spammy then I'll probably follow you back. Catfood Software (@CatfoodSoftware) will follow you backup using Catfood Follower. I've no idea if followers are Catfood customers or not so I want to follow everyone that signs up for Catfood updates.
Why auto-remove?
Twitter makes it hard to tell when someone you're following removes you. The auto-remove feature of Follower checks for friends who don't follow back and removes them. You can exclude users who you want to follow regardless.
How to use Catfood Follower
Follower supports multiple twitter accounts. For each account you can decide if you want to auto-follow, auto-remove or both. The screenshot above shows the settings for a single account.
You can add exclusions for both auto-follow and auto-remove. For auto-remove you can also set how many days to wait before removing a friend who is no longer following you. This prevents Follower from automatically removing new friends who haven't had a chance to follow you back yet.
Once you've entered rules for each account click the Test button on the main window. You can run the rules in test mode to see who would get followed and removed, or run in live mode to actually process the rules.
You can just run Follower manually when you want to run the rules, or you can use Task Scheduler to run it automatically. To schedule Follower (on Vista) run Control Panel -> Administrative Tools -> Task Scheduler. Click Create a Basic Task and follow the Wizard to set the schedule (i.e. once a day). If you accepted the defaults during installation then the path to Follower is "C:\Program Files\Catfood Software\Catfood Follower\Follower.exe". Running Follower with no arguments will automatically process the rules that you entered in Catfood Follower Settings. There is no display when Follower is running automatically.
Need Help?
If you have any problems or questions send me an email. If you have any feature suggestions please leave a comment below.
(Updated 2009-05-04 to 1.00.0108: Fixed a problem where new exceptions for an account were not processed, this led to Follower auto-removing exceptions. Also, the installer is now digitally signed.)
(Updated 2009-06-25 to 1.00.0122: Handle a twitter API bug with returning the correct number of friends/followers per page this is a critical update, added logging.)
(Updated 2009-07-21: Note that Follower does not follow new users for you. If you're looking to do this check out Twiogle Twitter Friend Adder.)
(Updated 2009-12-12 to 1.10.0061: Improved API limit handling, progress window during automatic processing, can now cancel and update. See Catfood Follower 1.10 for more information.)
(Updated 2010-03-16 to 1.20.0019: Fixed a bug related to location data in tweets. Added follow/unfollow limits to account settings. See Catfood Follower 1.20 for more information.)
(Updated 2010-09-02 to 1.30.0051: Updated from basic auth to XAuth - this is a critical update, added manual step for removing followers (unfollowing).)
(Updated 2011-11-06 to 1.40.0147: Added support for Klout and Twitter Lists. See Catfood Follower 1.40 for more information.)