For anybody who has the desire and opportunity to interact with something currently in production and truly alien-feeling, I warmly suggest IBM’s AS/400 (now iS

For anybody who has the desire and opportunity to interact with something currently in production and truly alien-feeling, I warmly suggest IBM’s AS/400 (now iSeries) OS/400’s filesystem. Library versus folders, logical versus physical files, integrated DB2 database is one of the many, many head-scratchers you’ll encounter until you suddenly “_get it_”.