MediaWiki extension, enabled via LocalSettings.php. This is done by adding
it to $wgValidSkinNames, for example:
-$wgValidSkinNames['mycoolskin'] = 'My cool skin';
+$wgValidSkinNames['mycoolskin'] = 'MyCoolSkin';
-and then registering a class in $wgAutoloadClasses called SkinMycoolskin, which
+and then registering a class in $wgAutoloadClasses called SkinMycoolSkin, which
derives from Skin. This technique is apparently not yet used (as of 2008)
outside the DumpHTML extension.