There are several ways to call your family and friends back home for cheap, or even free.

1. Skype
Skype is a great piece of software that allows you to make:
  • Free computer-to-computer calls, including video calls
  • Cheap computer-to-phone calls, either on a pay-as-you go basis or with an unlimited calling subscription
  • International call-in numbers that ring in on your computer: this allows you to have a local phone number in your home country that your non-tech-savvy friends and family can call to reach you on Skype
  • Call forwarding: this enables you to be reachable via Skype even if you are not online, by forwarding the call to your cell phone
  • You can combine the call-in numbers with call forwarding and the unlimited calling subscriptions: this means that you can have a landline phone number in your home country that forwards straight to your US cellphone, and all that for only the monthly subscription fees. It's a great setup for grandmas and other non-tech-savvy folk.
Download at www.skype.com.

2. Jajah
This is a website that allows you to make regular phone-to-phone calls which are free (between members) or cheap (between members and non-members). You log in to the website, type the destination phone number, hit "call", and then your phone starts to ring. Once you pick up, the destination phone starts to ring. Once the other person picks up, you can start talking. You can try this service for free for a while, and then will be prompted to pay ($2.5 are enough to maintain the free calling service between members). www.jajah.com.

3. Columbia Calling Card (CellularLD)
A cheap way to make international phone calls straight from your cell phone (with no need of a computer) is to use the prepaid calling card offered by Columbia. You can call over 220 countries, and the price for landline phones usually ranges from 5 cents per minute (Europe, China, South Korea) to 9 cents per minute (India). Calling cell phones is more expensive.
Register here: www.columbia.edu/acis/telecom/students/cellularld.html.