Usually, whenever I see something I like on the Internet these days, I "print to PDF" so I can have an offline copy. This is a great habit and I just do it out of routine these days.<p>So when I did it for this site, I was quite surprised that cmd-P didn't give me the standard Print dialog, but rather downloaded a pre-formatted PDF straight from the site, directly, instead.<p>Whoa! How do they do that? Cool feature, saves me a few clicks .. ;)