Learn how you can have your Mac speak its serial number in OS X Lion or Mac OS X v10.6.
- Make sure your Mac's volume is turned up enough for you to hear the serial number.
- Hold the Option key and choose Apple () menu > System Information (or Apple menu > System Profiler in Mac OS X v10.6).
- Press Command-4 (⌘4) or choose File > Speak Serial Number and your Mac will speak its serial number.
You can also find the serial number in the About This Mac window.