Scientific calculators that have formula/equation memory

[Chasfield]

The Casio fx5800p has the form factor of the graphical models of the same era but the display is not pixel addressable from the built in programming language. It is just a nice big multi-line text display that I am sure would be great for middle-aged eyes.

I have often thought about buying one for my collection but it would have to be a fairly expensive grey import to the UK.