Honestly this idea is not mine, but I realized his usefulness when I was customer of the Primus Canada...
What is the point:
If someone call my fongo number, and i was set the call forward (follow me) option earlier, that means that the call will ring on my cellphone with the original caller id number.
BUT, if there would be a setting option where I was able to choose if i want to forwarding the original caller id info or my fongo caller ID info it would means that the forwarded calls would show my fongo numbers on my cell phone.
Why it is important?
Because if i have FAB10 or whatever others named option with my cell phone provider, and one of the FAB numbers is my fongo number, that means i have unlimited free incoming call. Even nationwide, if my FAB numbers nationwide provided by the cellphone company.
I used that option by years with Primus earlier and I would very happy to use it again with fongo.
- It is legal ? of course it is. This is not manipulation with the caller ID because the caller info still connected to me by fongo.
- It is possible technically, of course because the primus (talkbroadband) still do that.
- It is good for the customers ... obviously !

- even if the servive would be available for those only who still payed their SIP config file from fongo ... in that case it would be useful for the fongo company also ...
So dear FONGO, please consider that small extension of your service.