For years, Sony Corp. has been scrambling to regain its position at the leading edge of music players. Now, that scrambling has produced an egg — a $399 dancing egg that flashes, rolls and flaps its plastic flippers to the beat.

Before you think the Walkman pioneer has finally cracked, it's worth noting that the Rolly is an amusing and somewhat educational robot whose moves can be programed using a PC. And the gadget certainly is a conversation-starter if your dancing hamster has run off.

But even if you need a robotic egg to be the life of a party, it's hard to justify shelling out $400 for the Rolly. Its controls are just too frustrating, its memory too limited and playback options too restrictive to justify the price. Plus, like all eggs, it's hard to figure out the point.

Rolly intrigued me as soon as I opened the box. It's slightly larger than a goose egg and wrapped by two large rubber tracks. The ends of the device turn easily, and caps on either end swing open to reveal two speakers. It can receive music wirelessly from a Bluetooth-enabled gadget. Songs also can be loaded from a PC.

It was easy to get Rolly rolling. With a couple clicks of the centre button, Rolly launched into a sassy performance of Avril Lavigne's "Girlfriend". The song and dance are among a few that come pre-loaded on the player.

Rolly and I did have some good times together. It was entertaining for a while, playing music and dancing around my office and living room floor with its little lights flashing and changing colours. I wouldn't want Rolly to DJ a party, though, as it is probably too quiet for a sizeable crowd and might get stepped on.

The lack of traditional controls can make it difficult to use as a music player. Volume is controlled by rotating the device on a flat surface or by turning one of its rubber wheels when holding Rolly on its side. Users move through tracks by rolling the device forward or backward, or, like the volume, by turning a wheel when holding it sideways. Songs can be added by plugging the Rolly into a computer.

And there's another problem: All that flapping and spinning tends to distort the audio. Keeping the player stationary is one solution — there is an included base for keeping Rolly stable — but that makes it as boring as any computer speaker.