Send and receive fax online 2011

There are a few online services that let you send and receive fax ( without installing a fax machine) but I like these two because they are built around Google docs.
1. ginzafax.com transforms your google docs account into a virtual fax machine with document sending and receiving capabilities.All received documents are saved in your google doc account.
It also offers email-to-fax which I personally like a lot. All these features are provided for a reasonable price but you may go for a free trial before paying anything.
2. Interfax.net/en is another internet-fax service intergrated with google docs. They don't provide a free trial and you will have to buyan initial credit of $10 to start using their services but this one provides an API so if you are a developer, you may go for it.
Both these websites cost on a per page basis so they are ideal for personal as well as official use.