lol, that's awesome. I wish I knew you could do that back in the day. Of course, I was never on yahoo chat but I would have been just to do this.
It was actually pretty easy to do, back then people were writing programs that allowed you to spam people on yahoo...pretty much how it worked was you create bots and had them constantly send PMs to users and eventually it crashed their computers and they had to reboot.
I learned how to do it from some guy in a chatroom (who was crashing people)...totally risky talking to some grown ass dude back then..but also downloading shit he sent to me.
All of my bots were named "TickleMeElmo" or "FischerPrice"
Then, they'd be numbered anywhere between 1-1000.
Before, when Yahoo banned you, they had an automated service thing setup where you can file tickets for issues with the program. You could use the same program I was using to crash people to create bots to file complaints on my behalf to get my account unbanned. Send enough complains and you are auto unbanned. It was ridiculous.
At some point, I guess they got a REAL person to ban me. I was so young and dumb back then, I didn't know I could just get a new IP address and start over.