[gitonup]

I've seen orgs run on Excel spreadsheets: one electric utility I worked for described their load in one massive Excel sheet. Where I think this analogy falls apart is that so many spreadsheets come to depend on macros (which my experience did, via ODBC), which makes them a meld between 2 and 3. I've definitely written systems at level 2 -- at the same company -- that have had way more ROI than the spreadsheet based system that was previously employed, but the spreadsheet could have employed macros to do the same thing.