While the main post was interesting enough, and has already garnered responses, I'm genuinely amazed that people pay for that level of "cron monitoring".
Looking around I see at least three services ("probyapp.com", "deadmanssnitch.com", and "cronwat.ch" - the latter of which has an expired SSL certificate).
FWIW one of the main reasons I've never used tarsnap is the pricing and the picodollars, it never felt "real" enough, although obviously it is completely transparent.
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