Shmuel, on http://jedi.informatik.uni-leipzig.de/ you got more infos on z/OS - os/390
Prof. Dr. Spruth (EX-IBM-Mainframe-Developer) has a public mainframe. for some tutorials(for his lectures) you get a "guest"-account. but for interessted people, like you, there is the possibility to get an advanced account. write an email to: [EMAIL PROTECTED] or [EMAIL PROTECTED] perhaps they can help you! Cheers, Matthias
