Free deskcalc software for windows

There are so many Calculators out there, but none of them is really equal
to a mechanical adding machine that nearly every businessman has on his table,
this one has it all plus capabilities associated with a Windows environment.
No more expensive paper-rolls .. all for free !
Features include a check-strip with comfortable text input per position,
correction possibilities (rectifying, adding and deleting values),
built-in formula interpreter, sales tax functions, cache (memory function),
percentage calculation, EURO-conversion, floating point- and fixed
point-calculation, subdivision into thousands, fast correction key,
display of the results in task strip and window title line, printing with
heading and date/time, Excel-export.
Memory arithmetic with any tape value and the running subtotal ,
Printing tapes on any available printer and to text files ,Porting
tapes to any clipboard compatible application ,One key sales tax closeout
with user set percentage , Automatic decimal point insertion ,Tape navigation
keys , User Guide to which the user can easily add topics, Optional tooltips
with help just by positioning the mouse cursor