If you ever have a need to send and receive faxes and do not want to make the investment in the hardware and perhaps a phone line, then doing faxing through email probably fits your situation. If you are looking for such as service then take a look at EFax.

They offer a free service which lets you receive up to 20 fax pages per month on your own unique fax number. If you have a small business, this is the perfect (and cost effective) way to allow your customers to communicate through faxing.

Unfortunately, the free service does not allow you to send faxes via email, as this requires one of their pay services. Still, if you want to receive faxes then EFax is worth a look.