I would call my mom first and tell her what a cool phone I have!! Then next my bud in Brazil so he could email me pics of the wonderful sites there to use as wallpapers!! But the real question is who would I not call and that is unknown at this time!!
I have been using Rebtel for the past 2 years and the VoIP service that they provide is ridiculously cheap,flexible and easy to use. (My $25 charge lasts around 6 months) I still have the app on my OG Droid.
I will call, as I always have, everyone in my family and my friends (especially on birthdays!)
I'd use the phone and credits to keep in touch with my friends, family, and associates in New Zealand, Botswana, Italy, Japan, and Brazil to name a few! Rebtel is a fantastic international calling service...