Hello, the 2.0 alpha version of MC Chunk loader is up at minecraft-dungeons.com today. Uses Three.js to load .mca files directly from a URL or from your local disk and show them in 3d. Can do a Minecraft x-ray style mode (showstuff=all, currently pretty show) or by default shows diamonds and dungeons.
Does not currently show all blocks, including some basic things like glass. Working on that stuff.