At a company I used to work for there were tales of an early admin guy handling all of payroll, employee directory, and tonnes of admin task data for multiple hundreds of employees in Excel. Guy was an Excel god.
It worked perfectly fine until it was move into a proper database with in house built portals to handle the tasks.
We used to have a prophecy that when the IT apocalypse hits, we'll be pushing our shopping carts around like in Cormac McCarthy's The Road; moving from company to company to fix the VLookups in their Excel spreadmarts