DocRaptor - As the only API powered by the Prince HTML-to-PDF engine, DocRaptor provides the best support for complex PDFs with powerful support for headers, page breaks, page numbers, flexbox, watermarks, accessible PDFs, and much more
FaxSalad - Pay-as-you-go, secure faxing.
PDFCrowd - Pdfcrowd is a Web/HTML to PDF online service. Convert HTML to PDF online in the browser or in your PHP, Python, Ruby, .NET, Java apps via the REST API.
Bitcoin Fax - Bitcoin Fax allows you to send a fax with minimal fuss. No sign up required. How it works:
PDFShift - Convert any HTML documents to high-fidelity PDF using a single POST request
Tiny Fax - The Township of Tiny is an environmentally focused, diverse family of communities providing a healthy lifestyle. (Account not monitored 24/7)