Very simple announcement script =]

Enjoy =]

on *:text:!add*:#: {
  if ($nick isop #) {
    set %timer_id $2
    set %timer_time. $+ $2 $3
    set %timer_chan. $+ $2 $4
    set %timer_msg. $+ $2 $5-
    notice $nick Just added announcement ID: $2
    notice $nick Time run: $3 secounds
    notice $nick In channel / To nick: $4
    notice $nick Message: $5-
    .timer $+ $2 0 %timer_time. $+ $3 msg %timer_chan. $+ $4 %timer_msg. $+ $5-
  }
}
on *:text:!del*:#: {
  if ($nick isop #) {
    .timer $+ $2 off
    unset %timer_id $2
    unset %timer_time. $+ $2
    unset %timer_chan. $+ $2
    unset %timer_msg. $+ $2
    notice $nick Announcement ID $2 is unset!
  }
}

on *:text:!list*:#: {
  if ($nick isop #) {
    if (%timer_msg.1) { msg $nick Announcement 1 is set! }
    if (%timer_msg.2) { msg $nick Announcement 2 is set! }
    if (%timer_msg.3) { msg $nick Announcement 3 is set! }
    if (%timer_msg.4) { msg $nick Announcement 4 is set! }
  }
}

on *:join:#YOUR_CHANNEL_HERE: {
  if (%timer_msg.1) {
    .timer1 0 %timer_time.1 msg %timer_chan.1 %timer_msg.1
  }
  if (%timer_msg.2) {
    .timer2 0 %timer_time.2 msg %timer_chan.2 %timer_msg.2
  }
  if (%timer_msg.3) {
    .timer3 0 %timer_time.3 msg %timer_chan.3 %timer_msg.3
  }
  if (%timer_msg.4) {
    .timer4 0 %timer_time.4 msg %timer_chan.4 %timer_msg.4  
  }
}

This is to your PopUps =]

Announcment
.Add:/msg # !add $$?="ID" $$?="Seconds(10800=3Hours)" $$?="Channel" $$?="Message"
.Del:/msg # !del $$?="ID"
.List:/msg # !list