RPN Rocks

I have been using my 11C for years and years now.
It's always there on the desk.
I really don't know what year I bought it, but it was in the eighties.
I can't think of any other Electronic item that still works from that era.
Nobody "borrows it" not many people even know how to use it. My boss occasionally does, he has an even older model the HP41C that he still uses daily. I just found out that a fellow blogger uses a similar style. The HP15C.
I wanted to look up the 15C and I remembered that there is a nice internet museum on HP calculators.