Apple's stock closed at its highest for three years following higher than normal trading activity Friday, as investors considered the company's success in the nascent digital music distribution market.

The dramatic return to fortune also reflected market rumours that claimed Sony plans to take Apple over – a rumour that has appeared form time-to-time since the late 1990s.

The news also comes as multiple sources report that Apple's newly introduced (to the US) iPod mini product is selling out in many locations, with Apple confirming it had taken pre-orders for 100,000 of the products in advance of the launch.

Commenting on the rumours, Creative Strategies analyst Tim Bajarin told Reuters: "[Apple CEO] Steve [Jobs] really understands what the pulse of the consumer market is, and he's got a strategy to go after that with an Apple brand,"

"To me, that's the last thing he'd want to do is get mixed up with Sony," Bajarin said. "They are just diametrically opposed to how they would run the business."

Neither Apple nor Sony have commented on the rumour. Apple stock stood at $26.74 at close of trade.