Use !savenick and !takenick. It's explained in the script but when I'm done updating it I'll expand on the intro.
*Quakenet doesn't have a public NickServ.
Oh yeah and Kirby helped with it. :P

raw 433:*: {
  nick Nicksaver $+ $rand(1000,2000)
  if ($me == %bot1) || (%bot1 == $null) { /set %bot1 $me }
  elseif ($me == %bot2) || (%bot2 == $null) { /set %bot2 $me }
  elseif ($me == %bot3) || (%bot3 == $null) { /set %bot4 $me }
  elseif ($me == %bot4) || (%bot4 == $null) { /set %bot4 $me }
}
on *:TEXT:*:?: {
  if ($1 == !savenick) {
    if ($2 != $null) {
      if ($notify($nick) == $null) {
        notify $nick $2 
        msg $nick Saved.
      }
      else {
        msg $nick That nick is already saved. To change your password type !changepass <Nick> <oldpass> <newpass>
      }
    }
    else {
      msg $nick Usage: !savenick <Password>
    }
  }
  elseif ($1 == !takenick) {
    if ($3 != $null) {
      if ($me == $2) {
        if ($2 == $notify($notify($2)) && $3 == $notify($2).note) {
          set -u10 %savednick $2
          nick Nicksaver $+ $rand(1000,2000)
          if ($me == %bot1) { /set %bot1 $me }
          elseif ($me == %bot2) { /set %bot2 $me }
          elseif ($me == %bot3) { /set %bot4 $me }
          elseif ($me == %bot4) { /set %bot4 $me }
          inc %bots 1
        }
        else {
          msg $nick Either that nick is not saved or the password is incorrect.
        }
      }
      else {
        msg $nick Usage: !takenick <nick> <password>
      }
    }
  }
  elseif ($1 == !changepass) {
    if ($4 == $null) { msg $nick To change your password type !changepass <Nick> <oldpass> <newpass> }
    elseif ($2 == $notify($notify($2)) && $3 == $notify($2).note) {
      notify -r $2
      notify $2 $4
      msg $nick Password changed.
    }
  }
}
on *:UNOTIFY: {
  if (%savednick != $nick) {
    if (Nicksaver isin $me) {
      if ($me == %bot1) {
        .timernick 1 0 nick $nick
        dec %bots 1
        /set %bot1 $me
      }
      elseif ($me == %bot2) {
        .timernick 1 0 nick $nick
        dec %bots 1
        set %bot2 $me
      }
      elseif ($me == %bot3) {
        .timernick 1 0 nick $nick
        dec %bots 1
        set %bot3 $me
      }
      elseif ($me == %bot4) {
        .timernick 1 0 nick $nick
        dec %bots 1
        set %bot4 $me
      }
    }
  }
}