First let me say, there are probably a million ways to do this, and probably 99% of them are the right way, including my way.
Site: WordPress. The need: Pop up a video using Lighbox for a registered user. Record the video was shown to the user. Record in usermeta table. Don’t show it again on subsequent visits. And lastly, make sure the video only plays on the Home page.
Works like a charm. The video pops up in a Lightbox window. Meets our needs.