Kasbah, thanks for the comment. Hash tables are easy once you figure out how they work and get over the intimidation they present with their own set of identifiers and aliases. It also seems you don't understand how the -z switch works, which is okay. The -z switch will unset your item after seconds. So doing:
hadd -z $nick jail 10
would be in lamens terms: add jail to $nick for 10 seconds, then delete.
A coding that I know some MUDs use, and the command I made for IRC was a command that is used to change things about certain mobs on the fly, like weight, str, etc.
You can also screw with people with it by executing procs, like @.bob->i_die() would cause the target, bob, to be killed instantly by running the i_die() proc.
Best I can tell you is look it up online, and more than likely, you'll run into many examples being MUDs.