I used to work in the engineering centre that supported PRESTEL and TYMNET Later on after PRESTEL was gone, BT security was visiting and freaked out when they

I used to work in the engineering centre that supported PRESTEL and TYMNET Later on after PRESTEL was gone, BT security was visiting and freaked out when they bumped into a developer who they had caught as a teenager hacking Prestel. Security wanted them fired senior management told them NO :-) Oh I also had a copy of the hackers handbook