Daniel of DailyBlogTips had recently posted about Downforeveryoneorjustme service that is simple check is website is alive. Way too simple and way too unreliable in my opinion but it had link to another service – Uptime Party.
What it does
Free service gets you monitoring single server every hour. You can choose what exactly to monitor like web or ping (or more specific stuff) and enter email address for notifications.
They are very willing to sell more (of course) but I wasn’t very interested.
You get short email with event and service that became unavailable. One more when it goes back online. So far I had no downtimes but it reacted once when site was loading slow for few minutes.
Simple to setup and use. Free plan lacks everything but the core feature. Still gets task done. I only wish some simple stats were included as well.