In those days credit card checking was done offline using Luhn algorithms.
So you could download a program to generate numbers, and use made up data, to get free illegal access to Compuserve. Sometimes the accounts lasted a few months before being closed.
I pretty much owe my career in tech to those programs. We were too poor for internet, but dad had a work computer at home. Fake CCs kept me online and let me upload the HTML pages I'd made offline, and chat to people who taught me everything.
There was an algorithm in a certain "Hacker Journal" to generate said numbers. Combine that with some valid prefixes (the first 4 digits, which indicate the issuer) and you'd pass most tests at the time.
I had a similar experience (about half as much.) Then there was a few times I dialed long distance BBSs..
My parents were so cheap they refused to buy a second phone line for years. In retrospect they probably enjoyed not being called by their friends or telemarketers.
