The reason I don't do this is that it would remove the pressure to make the content of the site be good.<p>One reason public transport is bad in most US cities is that rich people rarely use it.
This would make the HN frontpage much more useful to me, and also make me see more new stories.<p>It is pretty frustrating to keep visiting the homepage and 1/3 of it is stuff I know I have no interest in.
I'm pondering a Countdown Greasemonkey script, that would hide all articles I haven't clicked on within 5 minutes.<p>The problem is I keep coming back to procrastinate, and end up reading the irrelevant articles, too. Maybe auto-hiding them would help :-)
When you click read a story on HN it kind of "hides." At least it becomes less prominent than the other stories.<p>I often struggle trying to find links that I have read when there are a bunch of links that I haven't read.
Perhaps what would be more useful is an RSS feed. That way you get standard newsreader features like mark-as-read and show-unread and sort-by-newest for free.<p>Of course you don't get the sorting, but them's the breaks.
It's a good thing that all the "Ask HN" threads (more generally, all the threads without external URL links) are now aggregated under the "ask" link at the top of most pages, as the feature request thread<p><a href="http://news.ycombinator.com/item?id=363" rel="nofollow">http://news.ycombinator.com/item?id=363</a><p>linked to from the bottom of most pages seems to be missed by everyone these days.