Rang our voice line at work with a fax tone. Caller id said Faxblock.me and going to that web address let's you put your phone number in if you don't want to receive faxes. Judging by the whois information on that domain it's registered in the Phillipines. Not entering my number in that form, suggest no one else enters their number either. Businesses should be requesting permission before faxing you anyway, it's not an opt-out system