Sound can be an integral element in a brand's identity. Think about the chord you hear when you start up your Mac computer (or the sound of a computer booting up with "Intel inside"). Or what you hear before an HBO feature.
Sound creates an emotional connection between the brand and the audience, amping up the experience. Some branded sounds have become part of pop culture, like Nokia's original ringtone. In fact, sonic branding is nothing new--long-established brands like NBC have been using sounds as brand identity for decades.
Nestea uses four notes in its sonic branding. Coca-Cola has used sonic branding (OK, jingles) for certain campaigns. P&G is reviving and updating some of its classic brand jingles for a new generation. Are jingles going to be the remixed sonic branding for the 21st century?