I just posted about Amazon Mechanical Turk in the story immediately before yours - http://news.ycombinator.com/item?id=1704704 - but in all honesty, I have heard of a few people getting good results, although I don't know if you can target specific demographics too easily.
I think a good bet would be to pay for Facebook ads as they have pretty awesome demographic filtering. Check it out here: http://www.facebook.com/ads/create/
I think a good bet would be to pay for Facebook ads as they have pretty awesome demographic filtering. Check it out here: http://www.facebook.com/ads/create/