I created a Twitter bot called @dumpmon (recently suspended for no apparent reason) that scraped paste sites looking for password dumps and tweeting if one was found.

You can find the code here: http://github.com/jordan-wright/dumpmon.

Here are some stats if anyone is interested in what it collected over approx. 2 years: http://jordan-wright.com/blog/2015/05/26/two-years-of-at-dum...