One day faxes will become obsolete, but for now it's hard not to have a fax number because some people insist on sending you faxes. And some people insist on being sent documents by fax. Even though faxes haven't become obsolete I regard fax machines as such.
A fax machine can only be in one physical location, which means to send or receive faxes you have to go to that location. And if the machine runs out of paper then you won't be getting that important fax, will you? Same thing if the power goes out. The solution is to get an online fax service.
For years I've used eFax.com. I have a local number so people have the sense that they are sending the fax to a location in New Orleans (which for some reason seems to make people feel better). In reality the faxes go to some secure location that has high-speed reliable internet access. The faxes are captured as images and then sent to me by email. Sending faxes is the same process in reverse: I upload or email the document to eFax and they send it to the recipient's fax machine (or fax service).
I like eFax, but it's kind of pricey. The basic account is $16/month for 30 pages of sent faxes and 130 of received faxes. I don't think I've ever exceeded the minimums, but if you do it's an extra .10 or .15 cents per page, depending on if you are sending or receiving.
A friend of mine uses Myfax.com and, after checking it out I have to say that I'm impressed. It has all the same features as eFax, but at a lower cost: $10/month for 100 sent pages and 200 received. Also, when you receive a fax by email from MyFax there is a link to click if you want the fax to be flagged as a junk fax.