Skype has been down for 24 hours. There is an alternative to Skype. It’s called Gizmo Project. It allows the same free calls to other users of Gizmo (and other VOIP networks and devices that use SIP). You can also make very inexpensive calls to landline and mobile phones, and get a phone number in certain countries.
If you call often from a computer to a landline or mobile phone, the quality fo the call is much better than on Skype (at least for a Mac user). So I use Skype for calls to my other Skype contacts, but Gizmo for calls to regular phones.
The quality of calls between Gizmo users isn’t always good.