Mine

on *:QUIT:{ 
if ($nick == $me) { halt }
if (*.*.*.*.net iswm $1-) && (quit: !isin $1- && kill !isin $1- && local !isin $1-) {
if ($($+(%,netsplit,$1,$2),2)) { halt }
else {
set -u60 $+(%,netsplit,$1,$2) 1
/amsg [WARNING] NetSplit Detected between $1 and $2  }
 }
}