recently I start to built a business directory for personal use. In this business directory, I have try several theme options plugins, and by mistake I visit the URL:
Normaly, this file is accessible via the WordPress Network Sites installation, and it is responsible to display any WordPress option related with the current site.
Additional, this page allowing the end user to update some of these options from inside this option without accessing the database manually.
Now, I know that this file is also accessible via the normal WordPress installation, thus any admin is able to modify the site options on the fly.
Note: In case of serialized data, you get the message "SERIALIZED DATA" instead of watcing a serialized string. In this case you are not able to modify any information in the serialized data.