Even the *.ipt.aol.com ban was needed because one AOLer would use the HOST.ipt.aol.com rdns to ban evade and ruin it for everybody.
Prodigy / CompuServe / Blue Light gang checking in
Prodigy / CompuServe / Blue Light gang checking in
GEnie was another that was kind of fun. And I still can remember my CompuServe number!