#!/bin/bash

oldmd5="$(curl -s "$1" | md5sum)"

while :;
	do
	sleep 60
	md5="$(curl -s "$1" | md5sum)"
	if [[ $md5 != $oldmd5 ]] ; then
			echo "webpage changed"
			mail blah@blah.com
			oldmd5="$md5"
	fi
done