The Malawi-born Queenslander won gold as part of the 4x100 metres freestyle relay team on Saturday, swimming the second leg in a shock victory over defending champions the Netherlands in Olympic record time.
Each Australian gold medallist at the London Games gets to be on an Australia Post stamp and receives A$20,000 ($20,900) for their image rights. They also get an upgrade when the team flies home.
"I think this was the thing I was most excited about it," the 20-year-old Campbell told a news conference in a fit of giggles on Sunday.
"It was the first thing that went through my head when we touched the wall, I'm going to be on a stamp and I get to fly back business class.
"Terrible I know, but it's just one of those exciting things that comes from being a gold medallist.
"It's something that I've always really, really wanted and to finally achieve that goal is really, really incredible."
While all the Australian swimmers who swam in the relay heats get a medal, only the four who competed in the final have the honour of appearing on the stamp.
Melanie Schlanger, a heat swimmer for Australia's champion 4x200 team at the last Olympics, was delighted to make the step up into stamp class after swimming the last leg in Saturday's triumph.
"I was a member of the 4x200 in Beijing and I was in the heat team so I remember getting the medal and seeing the stamps and obviously the four finalist girls were on that and I remember feeling proud and sort of jealous at the same time," she said.
"I'd totally forgotten but ... I'm really rapt, I can't wait to see them and I hope I get a copy."
Campbell, who won bronzes in the 50 freestyle and 4x100 relay four years ago in Beijing, will also compete in the 50 and 100 freestyle in London.
The oldest of five children - her 18-year-old sister Bronte will also swim in the 50 freestyle - Campbell took up competitive swimming soon after arriving in Australia from Africa as a nine-year-old.
Although her progression from bronze in Beijing to gold in London would appear to be seamless, a bout of glandular fever wiped out her entire 2010 season.
"It's been an incredible journey, I never really set out to be an Olympian, I just started swimming and I just got better and better at it," she said.
"I took the first Olympics for granted because I was so young and I've really had to work extremely hard to get to this one and to get this result is absolutely incredible."
Libby Trickett's swim in the heats earned her a fourth gold medal in her only event at her third Games but the 27-year-old said she had no intention of calling it quits yet.
The 100 butterfly champion from Beijing, Trickett failed to qualify to defend her title after retiring for nine months at the end of 2009.
"I'm committed to keep swimming, to swim on, and I'd like to have a baby as well," she said.