In SAP we have plenty variations to read and maintain tables, but as soon as you are in a production system and want to make a fast correction, than it gets complicated. The transaction ZSY666 allows you to maintain almost any table and therefore can help in these desperate situations. This means you should only do it, when there is no other choice. This transaction can help when you are in trouble, but also can bring you in a lot of trouble.
Consider yourself warned and use it with care.
You can download the code from my downloads page.