OK, so in addition to SharpReader (thanks Sue) here’s another heap of ways you can keep an eye on / facilitate other people keeping and eye on your servers & sites.
Pingdom – Rocks the house… incredibly reliable (unless you’re using caching :/) so point it at something dynamic and give it your server tech’s mobile phone number :) – or just email if you’re feeling slightly less evil. Highly recommended!
Tweetscan and/or Terraminds – If Pingdom does’t tell you about it then your users certainly will. Real human testing! Put the feeds from these in SharpReader and get it to check them every 15 minutes (or whenever you compulsively click it)
Gmail – When your servers are down, so is your email :/ Don’t look so professional there then do you…. don’t, whatever you do put your server based email account into Pingdom for example (duh :)
Forums – More after the fact issues as they usually get hit by the initial issues, but still to be watched darn close, although preferably with a manual feedreader (like SR) as finding out about stuff 2-6 hours after it’s happening SUCKS.
After the fact:
Get your server techs to configure a WHM load review on each server to be emailed to you every day – so you can look back on spikes and alike and pull up patterns between days. Very useful also in the it doesn’t let you forget the issues you had that afternoon!
Google blog search updates, talk to people once in a while and remember, it’s never ever going to be just fine so don’t just back up your HDs but also yourself – at all times!