When Sony launched the PlayStation Portable (PSP) in the US last week, the Japanese consumer electronics giant was eager to position the $250 device as more than just a handheld video games machine.

Sony wants the PSP to be viewed as a complete portable entertainment centre capable of displaying digital photographs and playing videos and digital music. But while the PSP makes an excellent games machine with a superb colour screen and brilliant graphics, the device does not match rivals such as Apple's iPod and Windows-based portable multimedia devices when it comes to video and music.