When the Pearce man developed eWAY 18 years ago, he had $50,000 to his name. On Friday, he sold it to American payment technology services giant Global Payments for $US50 million.

Understandably, Mr Bullock feels a great sense of achievement from his brainchild that grew to doing 5.8 billion online purchases last year, or about a quarter of all internet transactions in Australia.

"What this shows is that you can do anything in Canberra," he said.

"It is a beautiful place and there are a lot of smart people here, which is why I'm going to stay and build something even bigger and better than eWAY."

True to the saying "you only have to get it right once", Mr Bullock's first entrepreneurial pursuit was trying to write software himself and sell it through PayPal.

But he soon discovered he could invent his own way of selling software, by assisting merchants to process online credit card payments.

When eWay kicked off, he set up his phone to beep with each new customer and would feel joy from each alert. Eventually, they became so frequent that he had to turn his phone off for some peace and quiet.

Years later, his customers would include Canon, Qantas, Puma and Nissan.

"My personal secret is to never, ever, ever give up on anything," he said.

"And you have to have a keen point of difference –if it's the same as something else, who is going to buy it?"

Running eWAY was a juggle of buying and selling, with a constant strive to make more money than the month before.

While admitting that the deal with Global Payments was a tough decision, Mr Bullock said he'd be "watching it forever" for now as a consultant for the company.

Global Payments chief executive Jeffrey Sloane said in a conference call on Thursday that the new partnership will create the leading payment technology company in Asia-Pacific with nearly 40,000 merchant customers in Australia and New Zealand.

Mr Bullock was eager to see his 80-staff company join one with more than 4000 workers and a market capital of about $8 billion.

But he was also excited about his new business, centify.com, which is an app/website set to manage commissions easily, motivate staff and pay them fast.

"It's turning work into a game," he said.

"I'm trying to turn it into Farmville."

Rolling from the success of one business to the birth of another would be daunting for most, but not for this businessman.

"I work harder than anyone but I don't consider it work, because I'm doing something that I love," he said.

"I think it's partly a disease to have that drive. I'll never get rid of it."