They long ago outlived every phone, calculator and computer of their generation. These days, you'll still see them prominently displayed on the desks of many certified financial planners.
But if you think the often scratched, dented and downright clunky-looking Hewlett Packard financial calculators are just sitting there as quaint collector's items, you would be very wrong.
"I bought mine 20 years ago and I still use it," said Delia Fernandez, founder of Fernandez Financial Advisory LLC in Los Alamitos.
"It's kind of like you are going to have to pry it out of my cold dead fingers to get me to stop," Fernandez said. She was kidding, mostly.
Financial planners still use them to quickly run everything from routine amortization schedules and compound interest calculations to 30-year mortgages and far more complicated problems.
Alfred McIntosh, who runs McIntosh Capital Advisors in Los Angeles, still remembers the 10-week course he took at UCLA many years ago to learn how to use his.
McIntosh considered the course a professional rite of passage.
"To this day, it still does calculations faster, and with more accuracy, than many of the other tools we use," McIntosh said.
Planners say the intricate RPN system -- Reverse Polish Notation -- the calculators use allow complex calculations to be accomplished more quickly, and with fewer steps.
"I'm so fast with mine," said Carol Somoano, a certified and fee-only financial planner with Asset Planning Inc. in Cypress, who uses an HP 12C.
"I feel naked when I don't have it and have to use something like Microsoft Excel instead," Somoano said.
Cecil Widdifield, another fee-only financial planner who also works at McIntosh Capital, said the HP calculators have maintained their appeal despite being "essentially unchanged over the last 20 years."
HP introduced RPN calculators way back in the early 1960s. In the 1980s, HP released its best-known version, also called the HP 12C.
As of last year, HP was still producing nine calculators for business, financial and scientific purposes that supported RPN.
But these are calculators that carry bragging rights that use a kind of reverse logic. The older, the more worn, the more faded the keys, the higher the esteem in which they are held.
Fernandez's favorite (she owns three) is of course her oldest. She proudly points out its dings, dents, scratches and faded areas.
But she remembers meeting a colleague whose HP calculator was so old and worn that it was held together with duct tape.
"He looked at mine and he said 'I win,'" Fernandez said. "In fact, I'm always a little suspect of someone who has one that looks new."
On a Google search, you can find HP 12C Platinum calculators selling for $69.99 to more than $200, depending on their age and condition. On EBay, the range is $79.99 to $115.