This question already has an answer here:
I've appeared here because, having bitched a bit about the some of the hot questions from this site, I thought I'd make an effort to pitch into the ordinary process and see what it's like.
It seems to that this site resembles some of the other 'inevitably subjective' sites; in the end, most answers will be opinion or personal experience, not objective, provable truth.
So, the second question I ventured to answer was 'Is there a professional way to refuse a time-consuming programming task given as a test for a job?'. Since it's a question about why companies that hire ask for certain things, and since, as it happens, I'm the CTO of a company that hires programmers, and does the very thing in question, it seemed to me that what I know about the process would prove useful. So I mentioned my job to 'back it up,' and make it clear that I'm not just making stuff up.
This did not go down very well with the OP :-)
Admittedly, I did not offer a direct answer to 'how to turn it down', but rather some background on why it happens and how the someone might approach it.
So, meta-persons, what's your advice? Continue to note my job when answering from my experience? Or not?