Mobile music players are set to become the must-have gadget for music fans.
A report predicts that people will buy more than 10 million players this year to listen to music while on the move.
The buying frenzy is being driven by the success of Apple's iPod and the reams of copycat gadgets aiming to cash in on its popularity.
The study by London-based Informa Media predicts that more than 21 million mobile music players will be in use around the world by the end of 2004.
The report predicts that people will plump for next-generation players that use a hard drive to store music tracks instead of flash memory.
Sales of Apple's iPod could make up a sizeable proportion of those sales.
Apple boss Steve Jobs recently revealed that the company sold more than 860,000 iPods in the three months up to 26 June.
The new iPods released early this week and the European debut of the iPod Mini could boost those sales further.
Informa expects there to be more than five million iPods in use around the world by the end of 2004.
It said that other firms likely to do well are Creative Technology, Sony and Dell.
Although the report predicts boom time for hardware makers, it is not yet clear whether the record companies will do well out of the rising interest in mobile music.
CD sales may not rise because many people have already converted their CD collections to a portable format.
However, the online music services that go alongside the music players could mean more money for music makers as people buy new tracks for their players.
One of the few factors that could dent the booming music gadget industry is incompatibilities between the formats used to make songs small enough to fit on different players.
These mean that tracks downloaded from one service or prepared for one player may not transfer to another.
From BBC News