i think the best switching phone is wholeswitch.
it could save up to 95%of your phone bills .
it's the cheapest international calls and calling card.

wholeswitch provides several services .
such as pc to phone /mobile Voip /callback/calling card/callshop/I_PBX/DID numbers/SMS services.
but i want to know the others about switching phone .
can you tell me ?
waiting for you...
http://www.cheap-international-callingcard.com