A website I need to access is currently down (port 80 connection hangs).
Is there a free online no-registration-required service that monitors websites that are down and then emails me when the site's back up?
I realize I could write this myself or use Nagios/etc, but it'd be nice to have a quick-and-dirty website for this.
I also don't want to set up constant or repeating monitoring. I just want to know when the site is up, and never hear from the app again (unless I revisit it and ask it to monitor another site).