Modified version of lastsync.pl for Arch (I use it with conky)

lastsync.pl

#!/usr/bin/perl
use Date::Manip;

$date = `grep "pacman -Syu" /var/log/pacman.log | tail -n1 | cut -c 2- | cut -c-16`;
$date = &DateCalc("Jan 1, 1970  00:00:00 GMT",$date);
$date = UnixDate("$date","%A %H:%M");
print "$date";