You can copy or convert terms between different taxonomies like categories, tags and other custom taxonomies wither created by you manually or present with some activate plugins and theme. Taxonomy Converter is the new WordPress plugin based on Categories to Tags Converter. The plugin allows you to copy (duplicate) or convert (move) terms from one taxonomy to another or to multiple taxonomies while maintaining associated posts.
Install and activate Taxonomy Converter plugin then visit Dashboard -> Tools -> Import screen and click on Taxonomy Converter.
There are many plugin which allows you to display related blog posts in WordPress. This tutorial is on a different kind of related posts plugin which allows you to select the taxonomy type and it shows related posts only from that particular taxonomy given by you. With this plugin you can set related posts display by taxonomies like tags, categories and other custom taxonomies created by you.
Using new I-Agree (BETA Release) WordPress plugin you can add custom text, links etc like terms and conditions which needs to be ticked before to make login from WordPress login screen. The plugin text is customizable, you can add all text there on login box or create a new Terms & Conditions page, copy its link and add there as shown in the following screenshot.