In the UK it was called "ex-directory" I guess short for excluded from Directory. In the 90's British Telecom, the defacto telecomes provider in the UK, introdu

In the UK it was called "ex-directory" I guess short for excluded from Directory. In the 90's British Telecom, the defacto telecomes provider in the UK, introduced a dialup service called Phone Base. Cant find anything about it online except this reference (https://www.lawinsider.com/dictionary/bt-phone-base https://www.lawinsider.com/dictionary/bt-phone-base), but it was possible to dial up, put in wildcard generic strings, select a dialling code and download massive tables of names, addresses & phone numbers. Natwest around the same time also had a dialup system, where you could do banking transactions over a dialup modem. It worked on the pretense you knew the account numbers you wanted to shift money to, its main security was the bank transfers were done offline, then their app, a frontend for a DUN terminal, uploaded the batch of bank transfers and then logged off within 30seconds or something like that. Now it was possible to access the Natwest system without using their frontend app on Win95, and just dial in and make the transfers yourself, your only constraint was the time limit and having a password to access the system in the first place. Security wasnt their strong point from what I could tell.