Bwa ha ha ha! tl;dr: Zero byte program sold for 5 pounds; when executed would instantly rerun last program run, making life easier for the user. 5 pounds divide

Bwa ha ha ha! tl;dr: Zero byte program sold for 5 pounds; when executed would instantly rerun last program run, making life easier for the user. 5 pounds divided by zero bytes is infinite profit. Well, if you ignore the unit mismatch. Well worth a quick skim.