I have been using hellofax for over six months now and it is truly awesome!
With hellofax and hellosign you can send and receive documents electronically and you can also electronically sign them prior to sending and/or request signatures from your recipients.
Ok, I know that this sounds similar to other technologies, but this one allows you to integrate all your incoming doc's with your Google drive account or your dropbox account. While other services have bits and pieces of all of the above technology, you have everything you need through one amazing technology and in my opinion, you can't beat the price.
I have quietly told everyone about hellofax over that past few months, but now they have gone one step further with their amazing technology and I felt like I needed everyone to know that this is a must have.
Now, you can actually receive documents into your GMail account and at the bottom where you see the attachment, you can sign them immediately. You will have the same options to "view" or "download", but you will now have an option that says "sign".
Here is the video explaining the GMail Integration:
This link provides a tour of the faxing and signing features as well as the google drive and dropbox integrations:
http://www.hellofax.com/info/tour#send_fax