Screwdriver, Chrome Ball, and Gear Sprocket

Finally, I have made something that really looks seamless and very close to a production level work! As you can see here, I have made a screwdriver and a gear sprocket. Before I get into the details, I would like to thank Micah Wagner for his great tutorials and personal help, without which I could have never made such photorealistic objects.
Here I have modeled these objects using simple polygon modeling, and used Booleans to shape the polygons for a desired look. Finally, I rendered it using "Mental Ray" in which I have used FG (Final Gather) with global illumination, HDRI (High Dynamic Ranged Imagery) and DoF (Depth of Field).
I hope you like my work. I would appreciate your constructive comments greatly.
Thanks.