Horizontal two finger scroll gesture test. Drag mouse to rotate model. Hold shift key or use mouse wheel to zoom it (canvas is matched to the browser window).

Two-finger horizontal scrolling touchpad gesture

In my netbook with Synaptics Gesture driver for TouchPads I can use in Chrome Two-Finger Scrolling gesture (up/down and left/right movements) to resize or rotate WebGL models
  var wheelHandler = function(ev) {
    var dy;
    if (ev.wheelDelta) { // Webkit
      yRot = -ev.wheelDeltaX / 30;
      dy = ev.wheelDeltaY / 30;
    } else dy = ev.detail;
    transl *= 1 + dy / 30;
  canvas.addEventListener('DOMMouseScroll', wheelHandler, false);
  canvas.addEventListener('mousewheel', wheelHandler, false);

They say that in Firefox DOMMouseScroll event has ev.axis field for horizontal and vertical scroll movement. Horizontal scrolling works in Firefox but I don't see this event in JS :(

WebGL Demos     updated 31 May 2011