One thing that you very rarely see written down in engineering calculations are error values.
I think it might be a nice feature to allow the entering of standard error values, and the subsequent calculation of resultant errors.
Errors are something that probably should be calculated and shown a lot more than they are.

Not exactly an urgent feature, but it might be something to think of for the distant future.

What do other people think of it?

Along those lines, was wondering if there is a plug-in available yet with statistical/probability functions... I haven't seen much discussion on this so I suppose the answer is no...

Great product though!

Actually I just posted a request for tolerances in variables, probably we're asking for the same feature