Yeah, mondine, there
is another topic which is about GMail skins, and it mentions another site, but nobody tried it out because according to the Terms of Service (of GMail), you are not allowed to skin GMail. Bad luck, FFVII.Cloud.182.
But there
is one think I noticed on
the site you mentioned, FFVII.Cloud.182. On the homepage itself, you learn that GMail skinning is a method they (the creators of the site) discovered on the
persistent.info blog, which is the site mentioned on the topic that mondine mentioned. You may call it a coincidence.