What is the best Nokia N95 VOIP software I can use to make free calls?

I want to take advantage of VOIP on my nokia n95, if i can find a company/software to use that is free I can move to a lower priced contract on my network and save some money.

I heard trufone is good but they are only free until november.
I tried fring but it only works with my orange internet on my phone which aint free.

It won't login when i try to use my home internet wireless connection

Related posts:

1. How to make voip calls on a Symbian 9 S60 V3 Nokia phone using a vpn on a broadband connection?
2. How to increase quality of VOIP calls while uploading/downloading?
3. What is the best software for recording calls made with VoIP phones in an office?
4. Is it free to make calls using VOIP on iPod Touch?
5. How to make international telephone calls to India using voip service, is there any provider for free service?