The Scots cyclist and team-mates Philip Hindes and Jason Kenny smashed the world record they set in qualifying as they successfully defended their title in the men's team sprint against France at the Velodrome.
The Duke and Duchess Of Cambridge, Prince Harry and Prime Minister David Cameron were all on their feet cheering as the British trio rode home in 42.6 seconds.
The win topped off a fantastic day as Team GB shot up the medals table to fifth.
And there was double medal success for Scots canoeists.
Aberdeen's Tim Baillie and partner Etienne Stott claimed Britain's first ever gold in the canoe slalom C2 event, while fellow Scot David Florence, also from Aberdeen, and Richard Hounslow took silver.
Later in the day there was more Scots joy when Luke Prentice, from Helensburgh, and partner Stuart Bithell got their Olympic career off to a "champagne" start as they surged into an early 470 Men's class lead on their first day of regatta action.
But the real Scots star of the day was Sir Chris Hoy and the emotion got to him. After receiving his medal, he wiped a tear from his eye on the top step of the podium as the National Anthem finished playing, with the partisan crowd singing along.
First Minister Alex Salmond sent a congratulations message on Twitter, the internet social networking site.
It said: "Congratulations to Sir Chris Hoy on his fifth gold medal. A legendary performance by Scotland's greatest Olympian. Truly inspirational."
Sir Chris said the success was "quite overwhelming". He said: "We knew it was possible – this hasn't come out of the blue.
"That last ride I dug deeper than I have ever dug before.
"I didn't want to let the boys down, they have been riding so well today.
"You can't overstate what it means to us in front of our home crowd."
The performance capped a remarkable 24 hours for British cycling after Bradley Wiggins became the first man to win the Tour de France and Olympic gold in the same year with victory in the road time-trial.
But Sir Chris must now wait until Tuesday's final day of the track programme to compete in his second event, the men's keirin, in which he is the world champion.
British cycling fans were later disappointed to see Victoria Pendleton and Jess Varnish miss out on a medal chance after being relegated from the team sprint event for a takeover infringement.
Aberdeen's Tim Baillie and David Florence were also flying the Team GB flag by taking home gold and silver medals. In the canoe slalom, Baillie and Etienne Stott lifted gold, with fellow Scot Florence and Richard Hounslow winning silver at the Lee Valley White Water Centre.
Baillie and Stott won in a time of 106.41 secs, followed by Florence and Hounslow in 106.77 secs.
Baillie admitted London 2012 would have been a success if all he had achieved was qualification for the canoeing C2 final, but after landing gold the paddler was on top of the world.
Baillie said: "Making the final, we were already pretty happy because we knew we would finish at least sixth.
"Then when we did our final run we thought that it was close to our best and we were semi-proud of it, as it was a good honest effort."
Another Scot, Luke Patience, got his Olympic campaign off to a near-perfect start in Weymouth.
Patience and his crew in the 470, Stuart Bithell, finished their opening race in second and then went one better in race two by taking victory.
That places Patience and Bithell right at the top of overall leader board with a two-point lead over Austria in second and a further five in front of Sweden in third.