The next time you receive a birthday card, don’t be surprised if you hear a song or sound when you open the envelope. Cleveland, Ohio-based American Greetings, which has been at the forefront of the card industry for 150 years, is bowing the new technology in a line called Music and Sound Envelopes. The colorfully designed envelopes feature a wide range of songs and sounds, from pop hits by artists like New Kids On The Block and The Romantics, to “Happy Birthday,” to people cheering and animal noises. The cards and envelopes retail for a suggested $3.49. For more information and samples, visit http://www.corporate.americangreetings.com/audioenv/audioenvelopes.html.