> I wonder sometimes how often small companies discover they've been running in the red instead of the black, because some cell got zeroed out, a sum didn't cov

> I wonder sometimes how often small companies discover they've been running in the red instead of the black, because some cell got zeroed out, a sum didn't cover an entire column This is a really interesting insight (actually obvious when you think about it). I'm currently working on a spreadsheet app and these kinds of observations are very interesting to me. I guess things like named cells/variables will help (instead of using $A$4 etc.). Range selection could also be more intelligent (it could actively warn you if a range selection seems to be missing a few cells of the same data type). Do you have any other insights here?