Is it possible to edit and digitally sign documents?

Hi.
Popfax has launched digital signature and document editing tools on its online fax interface for Enhanced Business Efficiency.
There are several ways to create a digital image of a signature:
Option #1. Upload signature
Option #2. Draw signature
Option #3. Type signature
Option #4. Upload signature by email
For more information about fax email and digital signature http://en.popfax.com