Is it real or is it CSS3? Amazingly, the above image was made entirely in HTML and CSS3 by Dylan Hudson. (via ★interesting)
Nasty Nets used CSS positioning to "embed" one YouTube video into another. "Be sure to hit 'play' on both YouTubes." Reminds me of the animated GIF mashups (more).
New design for A List Apart, the venerable Web design site, done with XHTML/CSS (of course) and Ruby on Rails. (via waxy)