I bought an HP41C in 1979, and I have been a fan of RPN ever since. I tossed the 41C back when I got my first Palm HPC and installed the "RealCalc" app. I'm g

I bought an HP41C in 1979, and I have been a fan of RPN ever since. I tossed the 41C back when I got my first Palm HPC and installed the "RealCalc" app. I'm glad that some of the modern calculator apps still support this mode.