Sometimes I want to have some means of structuring my tag cloud. For example, I tag a lot of researchers' home pages with their last names as tag. So I want to have all these last names together in one spot.
OpenURL aims to solve this 'appropriate copy' problem by providing a link to a copy of a work the user has a valid subscription to or to an open access version. BibSonomy allows to redirect requests to an OpenURL resolver chosen from the user. You can include the address of your resolver in the OpenURL field at your "settings" page.