This London bank raid seems impressive:
The investigation was started last October after it was discovered that computer hackers had gained access to Sumitomo Mitsui bank’s computer system in London.
They managed to infiltrate the system with keylogging software that would have enabled them to track every button pressed on computer keyboards.
Of course, it’s likely that there are lots more cases like this we don’t hear about. As Computerworld reports:
[Security experts] Cluley and Barnes said keylogging hacks are more common than thought, and they said the $423 million plot was probably the largest corporate case that had been made public. Both experts said it’s unclear what kind of keylogging was used.
The two speculate it could have been a physical keylogger dongle, installed by a cleaner (although that would mean the dongle would probably have to be retrieved somehow since any traffic through the company’s servers would be noticed. At least, one would hope so.)