Before Fifth Gate actually ran, I made a video to tease the concept and the worlds. I'm still very proud of it, and think it did a great job of communicating what I was looking to do with the game.
This was my first time trying to match my writing to visuals (outside of the occasional attempt at a comic book script) and I liked the process. I made a bunch of stick-figure drawings to storyboard it out, and then had an amazingly talented artist make actual art for the video. I recruited a staff member and my wife to do the voice acting, found some open-source music, and sent it all to a video editor who was interested in the game, and he put it all together.
The end result is something I've very proud of.