Google Voice is offering "priority invites" to students in United States with an .edu email address. “To get an invite, just visit google.com/voice/students and enter .educ email, Thats it! A Google Voice invite will arrive in your inbox within 24 hours. Keep in mind that only one invite will be be sent per email address and Google Voice is currently only available in US. It’s because college students in particular really appreciate getting their voicemail sent to their email, sending free text messages and reading voicemail transcriptions rather than listening to messages (especially handy while in class),” writes Google.
More Info: Google Voice on YouTube