Here's a quick and unobtrusive way to grab some information about your machine. As you may know, you can select "About this Mac" from the Apple Menu to produce a small window which lists your version of the Mac OS, your processor type and speed plus the amount of memory installed. You could click "More Info..." to launch System Profiler and gain more information, or try this.
Click the version number field and it changes to the OS X build number. Click it again, and your machine's serial number is displayed.
But the fun doesn't stop there! You can gain even more information from the login window (accessible when you first start your machine or after logging out). Clicking the field under "Mac OS X" there reveals
- Your computer's name
- The OS version
- Build number
- Serial number
- IP address
- Any available network accounts
- Date and time
We tested this under Mac OS 10.5.2, so if your experience is different, let us know what version of the OS you're using as well as what you found.