Here’s a couple:
Galleries that can be videos AND stills in any order (great for things like design agency portfolios);
Video player and image display have independent sizes – so a video could open at 360×140, and an image at 500×500, etc., sizes set in the gallery list of media vs. globally for the gallery;
A title AND a description field available, that could be styled separately.
All of the above would create a “media portfolio”, with a grid of thumbnails with titles and descriptions, and clicking a thumb could open a video, a screen grab of a web design, a logo design, etc. I haven’t found anything like this so far.