35mm Image Viewer
All-purpose.
"35mm" stuck for some reason, although "photo viewer" would have sufficed. Either way, this viewer displays photos sorted by collection.
A semi-transparent draggable menu shows icons, each of which represents a photo or video clip. Descriptions and file sizes are given where appropriate.
Image details are stored in multi-dimensional Javascript arrays for an independent (and fairly lightweight) app that's adaptable and fairly cross-platform friendly.