I have just finished work on a new WordPress plugin to add to the Your Brand group of products. We have called it Your Minder and basically what it does it stops people account sharing.
The idea of giving your login details to a friend so they can benefit from your increased access level is not uncommon in any system, especially those you have to pay for. We decided to write it as the perfect companion for the Your Members plugin which turns your wordpress blog into an (optionally) paid membership site.
Your Minder works by stopping logins from multiple IP addresses over a period of time. If multiple logins are detected in the (fully configurable) time period then you have the option for it to perform one of many actions including lock out both accounts for either a time period or until the activation link (sent via email) is clicked among others.
Yes, like many of the plugins i’ve written it’s not free but it certainly won’t break the bank at under a tenner (09/08/08) and will ensure a greater income from your members over time.
Take a look at the full spec and screenshots on newmedias to find out more! http://www.newmedias.co.uk/your-minder/