Ok, as i am currently using voip to call oversea...Will share here..
The cheapest rate + free 90 free call around the world upon each top up on www.voipcheap.com makes me loyal to them for few years..
U need to purchase credit of EUROS 10 & register an account.. Two ways to make a voip call

1. By downloading & install their softphone software & start making calls (landlines or hp worldwide)
2. SIP call- software such as Fring support SIP. Configure the SIP setting to point to www.voipcheap.com SIP server. Then, with WIFI turn on. U can use your iphone to make calls without a need of a PCs..

Hope this help

Yes,each time u top up 10euro u will get free call for 90 days.And one good thing is the credit will NEVER expire.Unlike skype,credit will expire n the charge is much more cheaper then skype.Visit www.voipcheap.com for more infor.

Great to c Fring is finally in app store.Had installed n enjoy using it.This ver had disable call via 3G/EDGE.Still I approciate the SIP call via WiFi

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Added on October 6, 2008, 4:15 pmHmm..v are talking about PC to landline or hp call.Not PC to PC call,how much I-talk or others telekom charge u for calling to UK or USA or Singapore?voip only cause u cents per minutes