How do I tag or save a thread for future reference?

Good question, I've wondered this from time to time, too.  I follow threads I've replied to, via "My Discussions", but some forums have a feature to subscribe to a thread, whether with notifications or without, but at least to have a list on the user's control panel with those subscription.

I'll be curious to see the reply.

on the right side of the screen below "users online" and "thread details" is the "thread options" menu. Near the bottom is the "favorite this thread" option. Clicking on that should do the trick.

Thanks, Stik!  I hadn't noticed that option in the right-hand menus.  I usually go right up to the profile group and go to my discussions, for threads I've posted in.

You're quite welcome Baron. I am not a fan of this new format. It is certainly not designed under K.I.S.S.- and I don't mean Gene simmons