Can I get Simon to periodically e-mail me to reassure me it is still working?

Yes, you can do this by using the Pulse service, with the Change filter. The Pulse service simply outputs the current date and time, so the output is always different. Then the Change filter detect that difference, marking the test as Changed.

You could also do this by adding a test for a frequently-updating page, like http://www.timeanddate.com/worldclock/, which changes every second.

Either way, check it at whatever frequency you want to be e-mailed, and have an E-mail notifier for changes. You can customize the e-mail message to say "I'm alive!" or whatever you like.