While the commenter above me has much more insight, I second.

This is really well done! I personally hadn't thought of this. I collect resources from HN all of the time and pile them up in an Instapaper account, but I organize haphazardly and poorly.

That said I'd add that if you can offer for registered users or anybody a regular caching or hard-copy option. To double up on that, offer pipelining of a cached data dump to a file on Google drive or Dropbox or any other redundancy endpoint. You could grow from there in usability. Or somebody could write a middleman service for that... fun's fun.

Great work, anyway.