There are already quite a number of free call online services but most of them probably will die off after some times. Here I just discover one that hopefully can give you some additional free call credits so that you can stay closed with your love one if they are far apart from you. Named as PokeTalk, it gives away free credits to all its subscribers, enabling them to make free calls, either from landline or mobile (depending on geography locations) to over 55 countries at zero cost.
Similar to other service providers, PokeTalk maintains its revenue by collecting advertising fees and some of the collections will be used to subsidy the international free calls that you made. Great thing is, no download or any additional peripheral is needed and it just works great on your existing landline/mobile number. What you need to do is just sign up for new account free here by entering your email address and password, then just login into the email account and click on confirmation link and that is all. By logging onto the website and key in the caller and recipient numbers, the system will help you establishing the voice communication session by dialing to both parties simultaneously.
Note that there is a maximum monthly quote that users can use which will be reset on the 1st day of every month. Not to worry about running out of credit, PokeTalk actually do encourage more people to join its network and hence is giving additional 1 bonus call for every new friend that you introduced, and additional 10 minutes talk time if they sign up for the free call. PokeTalk covers most of the countries in the world but in case you are not sure if your geography area is covered under this free plan, please check it out here.