Reposts in general are ok once or twice if a story hasn't had significant attention in the last year or so. But once a story has, we bury reposts as dupes.<p>If you read the Show HN rules (<a href="https://news.ycombinator.com/showhn.html" rel="nofollow">https://news.ycombinator.com/showhn.html</a>) you'll see that to qualify as a new Show HN there needs to be some major new development, not just a new feature—but that only applies after the "significant attention" test has been passed. If any of that doesn't make sense you're welcome to ask us at hn@ycombinator.com.
Re-submissions of a link are counted as upvotes of the original post, unless theres a certain amount of time between the posts. I'm not sure if it's ever been publicly stated what that amount of time is.<p>One common hack is to add some meaningless URL parameters at the end of your link, so <a href="http://google.com/" rel="nofollow">http://google.com/</a> becomes <a href="http://google.com/?hn" rel="nofollow">http://google.com/?hn</a><p>Please don't abuse this, though!