I also pointed out that the same could probably be done for page.cgi, so aside from the plugin comments, there's nothing overly PHP-specific about the topic.

The last fairly general question I asked in the PHP forum drew little interest there and the moderator said I should probably post it in this general forum, which I haven't done yet...

On a more productive note, I've started playing around with this and it is working pretty well thus far. I've added a new field to the Links database, modified the queries in generate_category_page() to grab either active or inactive links, and added to the category template to show a link to either the regular or virtual category, depending on which is currently selected. The same $cat_id variable is used, which makes things easy. I'm just using an extra 'rip=yes' variable in the query string to signify the dead links option.

The area I haven't tackled yet is making the virtual categories browsable (including page spanning). That could be a bit trickier, since functions like _title_linked() are set up a bit different with respect to globals. I don't see any reason why $IN can't be added to the globals to pick up $rip, though...

Dan