you could do something ez like this.. plus it would be a good idea to add a bit of flood control to ur snippet.

 on $*:TEXT:/^!slap\s(\S+)$/iS:#: { 
  if ($regml(1) ison # && !$hget(slap,flood)) {
    .hadd -mu3 slap flood yes
    if ($regml(1) == $me) { msg # No! }
    else { 
      var %slap large trout|large pig|large horse|large cat|Big Mac|large dog|computer|stolen car
      describe # slaps $regml(1) around a bit with a $gettok(%slap,$r(1,8),124)
    }
  }
}

or take out that msg # No!

on $*:TEXT:/^!slap\s(\S+)$/iS:#: { 
  if ($regml(1) ison # && !$hget(slap,flood) && $regml(1) != $me) {
    .hadd -mu3 slap flood yes
    var %slap large trout|large pig|large horse|large cat|Big Mac|large dog|computer|stolen car
    describe # slaps $regml(1) around a bit with a $gettok(%slap,$r(1,8),124)
  }
}