Blender 2.71 was just released with a bunch of new features. The most interesting ones for game development are split vertex normals (for hard edges) and normal map baking using a cage.
The cage avoids a number of problems with normalmaps on complex objects; read the Polycount wiki to learn more. Cage baking in Blender uses their relatively new Cycles renderer. An instructional video is here.
I think the result is quite nice. There’s room for improvements, but this is a good start. The lowpoly mesh for use in the game is 500 polygons – the original highpoly one was 200,000 polies.
I look forward to baking weapon models with this.
Edit; after some texture work, the crate looks like this