Sansonetti is a former Olympic road and track racer (Montreal 1976), but now operates a family engineering firm in West Heidelberg.
According to the Weekend Australian, he has spent 10 years and $3.5m of his own money perfecting his carbon-fibre monocoque machines.
But not just the Aussies rode BT. Leontin Ziljaard van Morsel of the Netherlands used a BT road bike to take gold in the women's time trial, while Theo Bos - also from the Netherlands - rode a BT in the men's track sprint.
Sansonetti 's firm builds aerospace components for Boeing and the Australian airforce.
"We started to tinker with the frame and the (bike side of the) business just grew," Sansonetti told the Weekend Australian.
"With the bikes doing so well at Athens I'm expecting a flood of new foreign orders. I've got no plans at this stage to mass produce the machines."
The Sansonetti engineering business employs 30 people, including three of Sansonetti's sons, and his wife.
British Cycling's no-brand bike is more modest at about $15 000 apiece.
The track bike was used for the first time at the Commonwealth Games. Chris Hoy's gold in the Kilo was won on the track bike branded as a 'UK Sports Institute' machine.
The UK Sports Institute Technology and Innovation strategy is a stream of government-funding for the development of sporting infrastructure and equipment.
The track bikew as part of the 'Athens Project', a specialist development project run by British Cycling to produce top-notch machinery in time for Athens.
The Athens Project was also funded by the GB Cycling Team's own lottery funding.
The bikes were designed by Dimitris KatSanis of the Derbyshire-based Advanced Composites Group (ACG), a resin, carbon-fibres and composites specialist which produces kit for Formula 1 cars, aerospace use and top-end sporting equipment such as tennis rackets and wakeboards. According to Philip Ingham, PRO of British Cycling, ACG produces carbon fibre frames of superior quality.
"It's hard to get commercially-available carbon fibre frames of this high standard," said Ingham.
"When it comes out of the mould, the frame is smooth and shiny and needs no remedial painting or filling common to many other carbon fibre frames."
Design work began in December 2001.
The bikes (and wheels and forks) will be offered to the public "in the medium, not the short-term," Ingham told Bikebiz.com.