Where can I find the Mountain Lion (Notification Center) notification sound?

I've been searching around for the little sound (the default one) when a notification is presented (on Mountain Lion Notification Center) but I can't find it.
Example: http://d.pr/a/P5xo (sound recorded)
Any ideas? Thanks!

In OS X 10.8 it's called burn complete.aif (or burn failed.aif–they are the same sound) and is found in /System/Library/Components/CoreAudio.component/Contents/SharedSupport/SystemSounds/system/.

To get into CoreAudio.component, right-click the file and select Show Package Contents.

The notification center uses the sound from your alert preferences, so you just need to check the sound being used in the system preferences and get it (or change it):

Go to the Apple menu;

Select "System Preferences" then "Sound";

The first tab shows the alert sound.

Note the name of the sound.

Go to /System/Library/Sounds and get/copy/change your file.

If you don't see any file in that location, and you do have sound files in the system preferences, that means you have the files hidden.

To show the invisible files, do this:

1. Open Finder
2. Open the Utilities folder

3. Open a terminal window

4. Copy and paste the following line in:

    defaults write com.apple.Finder AppleShowAllFiles YES
   

5. Press return; Now hold alt on the keyboard and right click on the Finder icon; Click on Relaunch

You will now be able to see any hidden files or folders. When done, perform steps from the begining, however, replace the terminal command with:

defaults write com.apple.Finder AppleShowAllFiles NO

Notice that you can have more info about setting up the notification center here: http://support.apple.com/kb/HT5362