The early HP Reverse Polish Notation calculators have a special place in the hearts of engineers and tinkerers as there are lots of projects involving them. They haven’t been produced in decades ...

This is an HP-41C pocket calculator, manufactured by Hewlett-Packard, that has flown on nine Space Shuttle missions in the 1980s. NASA purchased it from a local store in Houston, and installed special ...

The famous Tic-Tac-Toe game for HP-85 computers as well as HP-41 calculators. There is also a variant of the ... Still actively maintained and extended. HP-41C: There are many excellent HP-41 ...