Best value calling card with lots of free minutes

I have recently started using www.stanacard.com. It is awesome. It has the most competitive rates for calling to international destinations and has one of the best voice quality. One of the most innovative feature that stanacard has is that you can assign a local number to an international phone number and next time you wanna call your folks in India, just dial the local number and the phone in India will ring.
Last but not least, Stanacard gives a lot of bonus to the new customers. If you use a referral of existing stanacard member, you can get upto 20$ of free call time. Here is how it works
Fund your account with 5$, you get 10$ bonus time. Total 15$
Fund your account with 10$ and you get 20$ bonus time. Total 30$

So if you are convinced then go to the following link
http://www.stanacard.com/?ref=123879

Disclaimer: I must disclose that if you use my referral code then I get 1/2 the amount of bonus that you get.