A great utility for working with OBJ files and more
Pros & Cons:
Sculptris Alpha 6 is a free early version of a program that later went commercial. It's a great utility for working with OBJ files, tweaking them to your liking and then applying textures and colorization.
Of course Scupltris can also create 3D objects from scratch, beginning with primitive spheres and planes and then treating them like clay: pinching, creasing, inflating and elongating until the model arrives to your expected form.
There are helpful tutorials and a user forum to give you a leg-up. This is some truly exceptional and innovative software.
Sculptris was reviewed by Gizmos Freeware on based on version Alpha 6.