You might have spent considerable time skinning MediaWiki. It is, therefore, important to know your options when releasing your skin for others, and the ways in which you can restrict your skin's use by commercial entities.
By default, all of the graphics that you have created for your wiki will be in your copyright; they are your intellectual property. In the United Kingdom and other members of the European Union, this lasts until 70 years after your death, thanks to "Directive 2006/116/EC" and the consequent legislation. 70 years holds for the United States too, although there are some cases (for example, anonymous work) where the copyright expires after 95 years.
Creative Commons (http://creativecommons.org) has a range of...