It would be useful to add VoIP numbers to the database where available. This should be an up-and-coming area, though pretty restricted at the moment. It's possible for most VoIP users to call most others anywhere, totally free of charge. At the moment it's complicated. There are 2 basic ways:
1. If the called party has a fixed IP address from the Internet provider, that number can be called over VoIP. Exactly how depends upon the caller's hardware :-/ >:(. To call 123.186.204.123 a Grandstream VoIP box requires dialling *47123*186*204*123#; a Draytek VoIP router #123*186*204*123#. (For the expert, a non-static number can be called with the help of DDNS - the whole subject is long and complex).
2. If the caller and the called number use SIP providers (companies like Internet service provides), it is possible to call between many combinations of providers. The details, of course, are specific to each pair of providers (the computer industry loves standards, that's why there are so many of them).
and 3. And there are proprietary systems like Skype, which talk to other Skypeists but not SIP.

Having said all this, if a VoIP contact is published it's unique. How to call it is messy, not like picking up a phone and dialling a number: you have to work out what to do. (If it were easier everyone would do it, free; bad news for phone companies!).

As a start, for specialist Internet, email and VoIP company Gradwell:
SIP: sales@gradwell.com
SIP: support@gradwell.com
SIP: dsl-support@gradwell.com
SIP: porting@gradwell.com
SIP: billing@gradwell.com

(I don't use them, but can call them free if I need to).

Being a VoIP user myself, I am very interested in this.

Simply because companies MUST have VoIP numbers, their systems indeed have to go through some sort of box. And bigger companies now a days indeed I guess use VoIP for cheaper and more calls.

Be great if companies did indeed listed them, as they ARE free from these hardware boxes we enjoy using. I am able to dial these *47123*186*204*123#. It may look confusing, but its just an ip address really, just like any phone-number. :)

Skype as a proprietary system I don’t see much support here though. I have many Skype'd up friends, but I refuse to use Skype as I cannot just simply use the hardware to call Skype. If we could, it would be beautiful.

I look forward to any update or more comments here.

The more people who ask for this, the more likely it is that saynoto0870 will eventually include VoIP information. I don't see this happening soon. BTW, I wasn't able to contact Gradwell on the SIP addresses (from their website) I listed above when I tried, shortly after the earlier posting.

It might be a good idea for the time being if anybody with a VoIP contact for a company post it on this website, perhaps in this thread? I don't have any more.

Best wishes, pol098