Well, it's not automatic, but http://hckrnews.com/ http://hckrnews.com/ does have that functionality, since that's why I built it. I do store and highlight the

Well, it's not automatic, but http://hckrnews.com/ http://hckrnews.com/ does have that functionality, since that's why I built it. I do store and highlight the last visit time, which is useful for visits of a day or less. For a longer timespan, filter down (top 10 or top 20), then "Get Next Day" lets you page back through days you've missed. It's an interesting idea to make it adaptive, but I see a number of challenges. For example, you want just the highlights if you've been gone for a while, but perhaps someone else wants to scan through everything? Then there are the UI challenges -- making it obvious what is happening (and being able to change the default behavior) could be a challenge.