Faxaway

Overview
Faxaway is an internet fax sending/receiving service based in Seattle, WA. When you sign up for the service, you are given a phone number for fax receipt; faxes sent to that number will be emailed to you. You can also email documents in a wide variety of formats to faxaway, and it will fax them for you.

Reference

 * official web site
 * FAQ
 * receiving faxes - does not explain if there is any way to find your phone number for receiving faxes after the initial sign-up
 * sending faxes
 * fax broadcasting
 * user's guides
 * account status - apparently lists incoming phone # under certain conditions (maybe when you initially sign up?)