Claim your free 60 minutes of international calls per month if you currently have an Office 365 account (or with free Office 365 Trial, can cancel immediately - thanks @steven6)
Ongoing deal in case people weren't aware.
From Skype:
To claim your minutes, all you need to do is sign in or create a Skype account and we’ll do the rest. Say ‘hello’ to anyone with a landline in over 60 countries/regions or call mobile phones in 8 countries/regions, including the United States and Canada. See the full list of countries/regions below.
Both landlines and mobile phones: Canada, China, Guam, Hong Kong SAR, Japan, Puerto Rico, Singapore, Thailand, and the United States.
Landlines only: Andorra, Argentina, Australia, Austria, Belgium, Brazil, Brunei, Bulgaria, Chile, China, Croatia, Colombia (excl. Lex), Costa Rica, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Guadeloupe, Hungary, Iceland, Indonesia (Jakarta), Ireland, Israel, Italy, Korea, Latvia, Lithuania, Luxembourg, Malaysia, Malta, Mexico, Morocco, Netherlands, New Zealand, Norway, Panama, Paraguay, Peru, Poland, Portugal, Romania, Russia, Slovakia, Slovenia, South Africa, Spain, Sweden, Switzerland, Taiwan, Turkey, United Kingdom, and Venezuela.
Skype minutes are not included with Office 365 in Algeria, Bahrain, China, Egypt, India, Korea, Kuwait, Lebanon, Libya, Morocco, Namibia, Pakistan, Qatar, Taiwan, Tunisia, and United Arab Emirates.
Note that special, premium, and non-geographic numbers are not covered by Skype minutes. Additionally, it isn’t possible to place emergency calls.
Repeat after me: "It's not worldwide if it excludes a bunch of countries."