I suppose this is belated, but I'm just updating it now. v1.75 is now available here:http://www.skytopia....m/software/opalcalc/
The original post for it here at DC is here:https://www.donation...ex.php?topic=30578.0
This is an insanely, wicked amazing calculator. Once you try it, you'll wonder how you ever survived without it. It beats the b'jeez out of any normal calculator program. Type what you want, and get an answer.
I absolutely cannot recommend this program highly enough. It's on my very, very short list of true "MUST HAVE