Pdfcrowd is a new online application that turns any web site into PDF format easily with a variety of options, including the ability to set margins, encrypt files, or disable copying and printing. It also allows you add a simple a href link to your website to helps readers and users download your pages as pdf.
Add a Download as PDF Link in your Website
Provide a PDF copy of your web pages. Copy and paste the code below and paste into your pages or template. It creates a link that converts the containing page to a single page PDF using the HTTP referrer.
<a href="http://pdfcrowd.com/url_to_pdf/?height=-1">Download this page as a PDF</a>
For eg: Here is a demo (of this page) : Click Here.
Convert HTML (Webpage) into PDF with Options
Pdfcrowd’s got a lot more options that set it apart. The service is relatively straightforward. You’ve got a variety of ways to input your source: you can enter a URL, upload a HTML or TXT file (TXT is not officially supported, but it works), or enter HTML code directly.

Link: http://pdfcrowd.com/#convert_by_url+with_options
If you choose to enter HTML code, Pdfcrowd translates the code into PDF for you, and there’s a WSISWYG editor available for making tweaks. After you set your options, hit the button to convert your file.
