I almost think that you are intentionally trolling, but I will link to and quote from the HN guidelines in response to your comment:

http://ycombinator.com/newsguidelines.html

On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity.

If your account is less than a year old, please don't submit comments saying that HN is turning into Reddit. (It's a common semi-noob illusion.)