OmniOutliner has had some kind of formulas for a very long time, however they work like an actual spreadsheet, where each outline row can have additional number

OmniOutliner has had some kind of formulas for a very long time, however they work like an actual spreadsheet, where each outline row can have additional number and formula columns. I don't think it's all that useful, outside of some basic "making a shopping/packing/project list" type calculations. It's worth checking out if you're interested in the history though.