How important are calculators?

Of those of you who use calculators in your daily lives, how many use algebraic and how many use RPN? Do you care which you use, i.e., do you choose algebraic over RPN or vice versa, or is it simply a case of what you grew up with?

Do you imagine that there would be a value to having Mathcad run on a hendheld device, one with a decent interface and good graphical display?

Rich
http://www.DownEastEngineering.com/