You can easily set the background tune of Nokia Lumia advertisement as ringtone on WP7 devices.
Nokia Lumia Ringtone is a free app for Windows Phone 7 offering 5 Nokia Lumia tunes that can be set as ringtone. Simply download the app, play the Lumia tune you like, and set it as ringtone.
Although each ringtone is an edit of the original version, the app does a solid job in bringing customized tones on our phones for free.
Steps to Follow:
Size: 4 MB. Works on HTC, Nokia, Dell WP7 devices. Requires Windows 7.5 or higher.
Related: First Polyphonic Ringtone From Nokia.