Michael Arrington over at
TechCrunch noted that Skype last week began offering real-time language translation services for Skype voice calls. The service is offered through a partnership with Voxeo and Language Line Services, and 150 languages are supported.
It's easy to use and costs about $2.99 per minute (using SkypeOut credits). You don't need to schedule a call. You'll get an interpreter in about 45 seconds after the initial request.