http://www.improvely.com, http://www.w3counter.com, http://www.dialshield.com and a couple others are mine alone. I support around 90,000 users across all the sites. This is what I do for a living.
p.s. improvely (which I knew about before) and dialshied (which I've now bookmarked) work great but I got this on www.w3counter.com:
Oops! An Error Occurred
The server returned a "500 Internal Server Error".
Something is broken Please e-mail us at [email] and let us know what you were doing when this error occurred. We will fix it as soon as possible. Sorry for any inconvenience caused.