Here's a simple way to use voting to clean up some crap:

 1. In the search box, enter:  votes:0 answers:0
 2. Click the "Newest" tab and scroll down until you're looking at questions that are at least a day old
 3. Click on one that looks bad (based on the excerpt), read it.
 4. If it really is bad, vote it down.

After 30 days, questions with no answers and negative scores are automatically deleted.

The "official" meta post with the auto-deletion rules was recently updated: http://meta.stackoverflow.com/a/92006/130540