The mirror modifier allows you to mirror any action you take on an object to the adjacent axis. This is great tool for creating symmetrical objects. It's commonly used when modeling humanoid type creatures. This tool will save you a lot of time you would normally spend manually adjusting both sides of an object for symmetry.
The pose library in Blender allows you create set of predefined poses for your armature. You can use these poses for things such as facial animation or walk cycles. In this video I give you an introduction to the pose library and show you how easy it is to create a simple animation with poses.
This video gives you an introduction to armatures in blender by showing you how to create simple skeletal system. Armatures can be used to deform a mesh and manipulate it's pose which allows for a quick way to create animations.
Note I made a mistake in the video. The armature should be the parent of the object in order to make it influence the object. I accidentally said make the object the parent of the armature which is incorrect.
A very quick and efficient technique for drawing clouds in GIMP. This same technique can also be used to draw smoke too.
This tutorial shows you how to model a simple low poly tree in Blender. The technique used here is simple to follow and can be easily modified to create an array of low poly trees with different variations. It also doesn't require any clean up and is game ready.