Up to 100 people will become millionaires on the night of the Olympics opening ceremony when a special National Lottery draw takes place.
The one-off draw aims to smash the world record for the most millionaires created in a single night.
Lottery operator Camelot said more than 20 million extra playslips ready to take players' lucky numbers have been despatched for the event, while more than eight million metres of ticket roll are ready to be transformed into tickets for the draw.
The National Lottery Line will be open until midnight on Friday ready to greet lucky ticketholders and will have four times the normal level of staff on standby to take players' calls.
Tickets have been available to buy in advance, with other EuroMillions draws, but from today players can purchase a line just for the special EuroMillions Millionaire Raffle.
A National Lottery spokesman said: "This will be a massive night for the nation and this draw is going to make it even bigger. We will see a stunning world record set as 100 players become millionaires overnight. We urge players to get their tickets early to ensure they don't miss out.
"National Lottery players are playing a key role in the London 2012 Games, helping fund both the infrastructure and venues, and provide life-changing support to athletes.
"This special one-off draw celebrates their role in helping bring the Games to London."
The National Lottery has created more than 2,800 millionaires since 1994 and already holds the world record for the number of millionaires created in one draw, set after 25 millionaires were created in the EuroMillions Millionaire Raffle draw on Christmas Eve 2010.