The K3D engine ("Kevs 3D", no relation to the k-3d library of similar name) written entirely in JavaScript and HTML5 canvas. All 3D maths is hand cranked and rendering performed using the nifty Canvas APIs - no 3D plugins or Canvas3D extensions required.
The code for the simple-but-fast 3D pipeline was originally written in C/C++ back in the coding dark-ages of 1996, converted to a very-nifty-for-the-time-thanks Java 1.0 Applet in 1998 (the first 3D in Java that I know of! and well before the Java3D APIs existed) and recently converted to modern JavaScript and HTML5 Canvas.
Runs best on Chome, Safari and Firefox browsers. Chrome 5 is the fastest!
Objects can be displayed as points, wireframe, solid polygons, textured polygons and shaded using plain colour, depthcued (z-order) or light-sourced - things can be rotated around and moved about to make cool demos. A simple linear-additive lighting model with any number of coloured lights can be applied to solid objects.