I've been a fan of [Illuminatus!] ever since I read it at age 13.
Since learning [HTML], I've always wanted a <fnord> tag in html.
Its purpose would be to make text one shade darker, or perhaps to hide a [subtext] as well.

The <fnord alt="We own the world.">Bavarian Illuminati</fnord> do not exist.

would appear in your browser window as

The Bavarian Illuminati do not exist.

only with perhaps a slight shading of the words "Bavarian Illuminati." If you let your pointer hover over that particular phrase, the following would appear at the bottom of your browser window where link destinations usually appear:

We own the world.

Hail Eris!
5th writeup in an [Illuminati|Illuminatus!] node!
All hail Discordia!

Fnord (idea)