If the sysop is stupid as shit on a WWIV board and have ARJ, set up 
your own autoexec and config sys or whatever else you want, upload it, 
extract the files from it, then extract them again, ARJ will say 
something like "File already there, Skip, Overwrite, Rename?" So of
course, you say rename, and put in the whole path like c:\autoexec.bat then
tell it to overwrite.. upload like a small com to reboot the system, so then
it will execute your new autoexec, which you can make do whatever you
desire! Maybe making a new WWIV userlist so you know the bbs's passwords 
might be fun, install that, then reboot tha thing, call back and wham... 
full access... Its stupid and old way to hack it but usually works