Every now and then I see forum posts asking how to get the forward of the camera or of a mesh. I think I've come up with a simple way to do that with Node.getDirection. Here's a PG demo:
http://www.babylonjs-playground.com/#1CSVHO#6
(move the camera to see that the sphere stays in front of it)
edit:
I added Vector3.Left and Vector3.Right:
http://www.babylonjs-playground.com/#1CSVHO#5
moving a mesh forward:
http://www.babylonjs-playground.com/#1CSVHO#7