Not too sure if this is what they meant as I've not tried it and I'm not going to, but if there's too many users in a channel would you get flooded off by who'ing the channel?

Maybe something like

Code:
alias who. {
  var %x = 1, %y
  while (%x <= $nick($chan,0)) {
    inc %y
    .timer 1 $calc(%x + %y) who $nick($chan,%x)
    inc %x
  }
}