Simple HTML to PDF Converter
html-pdf-online.com
html-pdf-online.com
And it literally does nothing differently ...
[1] Full disclosure: I know the guys behind DocRaptor. It's probably a great service without my bias, but there's almost definitely some bias.
It supports mostly all of CSS 2.1, CSS 3 support for rounded corners etc… would be nice though. The fact it respects page breaks is a huge bonus.