Post Since Last Visit I don't think works correctly. I was here this morning, left for about 30 minutes, came back and that link shows posts made 2 hours ago.

The link is rather smart. It uses the database to keep track of when you last read actual threads in each forum. In other words, if you stopped by DaniWeb but didn't read anything in the C++ forum, then when you ask it for a list of new posts in the C++ forum, it's going to give you a list from the last time you actually visited the C++ forum, not the last time you visited DaniWeb.

I think this is a great idea, but 3 pages of new posts, most of which I'm not interested in perusing at the moment makes it somewhat unwieldly. If they can be sorted by FORUM-INDEX + FORUM + TIME it might be easier to use since I for one go to the C++ forum 1st, then the rest of SoftwareDev. At least what we're interested in would be grouped together.

I'm confused by your question.

Currently the list of "New Posts" and "Today's Posts" are listed in chronological order. It would be easier to find posts we are interested in if the sort order instead was

MAIN GROUP (software dev, web dev, etc) then
FORUM then
TIME

for a 3-field sort order

Just noticed the problem in the attached file -- how "C and C++" is visible behind "Post since Last Visit". Using IE6 on XP

Unfortunately that's a bug that I spent almost an hour trying to fix yesterday to no avail. I'm going to take a little break from it until I come up with another idea to try. Essentially playing with the z-index CSS property should fix it but it doesn't and I don't understand why not.

Is it possible to add unanswered threads to the drop-downs?

Looks like you got it fixed Looking good now.