Hacker News
- What Is RPN? Why Did/Does HP Use RPN? Learning RPN (1999) https://www.hpmuseum.org/rpn.htm 117 comments
- The HP Garage (2009) https://www.hpmuseum.org/garage/garage.htm 19 comments
- HP Calculator Programming in RPL http://www.hpmuseum.org/rpl.htm 2 comments
Lobsters
- The Museum of HP Calculators https://www.hpmuseum.org/ 4 comments hardware , historical