It is a very simple script to make, i made the example below in less than 15 minutes
I just compare $version with the first line of http://www.mirc.co.uk/versions.txt

if a new version is available i supply a link to http://www.mirc.com/get.html in the status window.

Usage: Just type /mirc.update and press enter

Code:
alias mirc.update {
  sockclose mirc.update
  sockopen mirc.update www.mirc.co.uk 80
}
on *:sockopen:mirc.update:{
  if ($sockerr) { echo $color(info) -s *** Socket Error - $sockname - ( open ) | return }
  sockwrite -n $sockname GET /versions.txt HTTP/1.1
  sockwrite -n $sockname Host: www.mirc.co.uk
  sockwrite -n $sockname $crlf
  unset %mirc.update.version
}
on *:sockread:mirc.update:{
  if ($sockerr) { echo -s $color(info) -s *** Socket Error - $sockname - ( read ) | return }
  var %update | sockread %update
  if (%mirc.update.version == 1) {
    tokenize 32 %update
    if ($version < $right($4,-1)) { echo $color(info) -s *** Update available - $1- - http://www.mirc.com/get.html }
    else { echo $color(info) -s *** No update available }
    sockclose $sockname 
    unset %mirc.update.version 
    return
  }
  if (!%update) { %mirc.update.version = 1 } 
}

--
GamerTag: maffew
How many hax0rz does it take to screw in a lightbulb? 1337