More than 200 gamers have queued for hours in the rain to lay their hands on the new Xbox 360 game console.
More than 200 queued in Oxford Street ahead of the midnight launch
Some waited for up to nine hours amid fears the new generation console is set to sell out after retailers warned of a shortage ahead of the launch.
Doors opened to customers at midnight at Game's flagship store in London's Oxford Street.
The Xbox 360, made by Microsoft, is one of the most eagerly-awaited consumer electronics debuts of the year.
XBOX 360 SPECS
Three IBM PowerPC-based 3.2 GHz cores
One teraflop overall system floating-point performance
ATI graphics chip with 10MB of embedded DRAM
512MB of 700MHz GDDR3 RAM memory
Detachable 20GB hard drive
Built-in Ethernet port
Games supported at 16:9, 720p and 1080i, anti-aliasing
Streams media from portable music devices, digital cameras and Windows XP PCs
Supports up to four wireless controllers
It is vying with Apple's iPod and Sony's PlayStation Portable (PSP) at the top of many people's Christmas lists.
It is the first time that a console maker has launched a product almost simultaneously across the world and the ambitious plan has led to supply problems for Microsoft.
The technology giant has been forced to defend itself against accusations it has failed to provide enough consoles ahead of Christmas.
Some 300,000 Xbox 360s are likely to be available for Friday's European launch, though demand is expected to far exceed this.
It also sold out quickly when it was released in the US last week, with some machines subsequently appearing on the online auction site eBay for inflated sums.
Waiting for hours
The retail chain which includes Currys, Dixons and PC World has said it will have a limited number of the basic Xbox 360 package in stores.
Tesco also said it would have limited supply of the consoles on sale in 130 of its largest stores from midnight.
In the UK, the first in the queue to lay his hands on the new console was Kevin Sage, 33, of Sydenham, south London.
He had waited outside the store since 1445 GMT.
"We have been waiting in this queue for hours and hours and now I can't wait to get home and play this game," he said.
"I've made so many new friends through this, it's a surreal experience and I will remember this for the rest of my life."
Also in the queue was Richard Tiah, 22, of Enfield, north London, who had been waiting since 1500 GMT.
He said: "Demand has been so high it's impossible to get it unless you pre-ordered and got here tonight. There's nowhere else you are going to get it off the shelves unless you are in this queue.
"I'm buying it for myself as an early Christmas present."
Video games are hugely popular in the UK. More than 40% of British household, accounting for 11 million homes, own at least one games console, according to Jupiter Research.