Licence in Node

It's currently designed so the license is only displayed as part of the node if the node's license is different than the site's. I could add the feature you're suggesting as an option. Is there any particular reason the site footer isn't good enough since it displays below every node?

Also, technically the site footer is a div with an id. You could modify your theme to change the location of this div. Since the div can appear immediately below the main page content it's possible to have it appear right beneath a node.

The copyright in my site works like this:

1) In www.wikinerds.org everything is (C) All Rights Reserved unless otherwise mentioned.
2) In portal.wikinerds.org everything is CC-By-SA2 unless indicated otherwise.
3) Every node has its own licence

So, there is a cascade of three copyrights: ARR->CC->node. if there is no node copyright, then the default CC copyright applies. If it isn't in portal.wikinerds.org then the ARR copyright applies, unless otherwise mentioned (practically most other content is CC/GFDL too).

In my theme the Site Footer is displayed at the far bottom of the screen, not under the node. I don't like customising too much my installation because I want to be able to upgrade easily (i.e. if I customise I would have to remember what files and code I have added and where = too much work). Also, I am too busy to learn the API/internals of Drupal right now, although its code is generally easy to understand and I would like to learn it sometime.

In practice, nobody would see the node copyright in the footer. In my view, the footer applies to the site and to nodes without their own notices.

Also, I am afraid that people would just copy-paste the node content without referencing the author and the licence. For this reason I want every node to have its licence displayed as normal text (i.e. inseparable from the node text), so that when people copy-paste they also get the licence.