I enjoy browsing the "Hot Questions" on StackExchange. Typically the questions posted there aren't nearly as interesting as the answers. I'm always surprised by the depth to which questions are answered as well as the thoroughness with which some users investigate their answers before posting them.
Ethics
During review, I found a superior solution. What now? The top-voted answer explores the possible options the asker has for a difficult situation and explores the reasoning behind why the asker would choose each.
Biology
What could cause a forest of bent trees? An interesting explanation for a phenomena I've often seen called "unexplainable".
Interpersonal Relationships
How do I deal with a very manipulative employee who doesn't do his work? [duplicate] When someone manipulates everyone but you, what do you do?
Optics
Are there any secrets in lens design? How do you keep the design of a physical object secret?
Software
How does malicious software encrypt victims' files? Malware is a business, so malware writers make business decisions such as optimizing their code.
Electronics
Coaxial cable, resistor and oscilloscope Sometimes you have to check your assumptions before you make any conclusions. This asker was probably using a different resistor than he thought he was using, so his results made very little sense.
Photo by Raymond Bryson