Sorry if this suggestion has already been made (I did check but didn't see it) or if there is already a good way to do this (again I checked and didn't find one) but:
I've been spending a lot of time recently looking through the various add ons and third party resources people are selling. Some have been great, one or two haven't. This led me to make the decision to start only buying paid resources that have a working demo available, partly so I can see how the product works, and partly so I can see whether the author felt their product was worth the time and effort to put up a demo of.
The problem now is that I have to click on each resource that looks remotely interesting, then crtl+f to search the OP for the word "Demo" so I don't have to scroll around looking for one, then if it doesn't have one I just close the page and forget about it. What I would love is a simple way to filter resource threads so I only see threads that contain demos of the products they are selling.
Thanks for your consideration.