Each year as new films are released, I'm always amazed at new advances and groundbreaking achievements in CGI work. Not that I'm a huge fan of excessive CGI effects(I'm much more impressed by effects shot in camera), nevertheless I can appreciate the amount of time and work that goes into the film during post production to achieve those effects. If the effects are pulled off right, they can greatly contribute to the overall look and feel of the film. In my opinion, The Lord of the Rings trilogy boasts some of the most impressive and stylish CGI effects of any film to date. More specifically, the post production logistics of producing a film such as The Fellowship of the Ring could be enough to make you pull your hair out. However, with the right crew of capable people all coming together with the goal of making the film a reality, a masterpiece of cinema can be the product, even with a lot of CGI work at play.
An outstanding example of the capabilities of CGI can be found in the creation of the character Gollum.
In order to create Gollum for the film, it was first neccessary to decide what he was going to look like. This decision was a collaborative process between the director, the animators and the artists. They spent months mulling over various physical details of the character and outlined what look to give his face, his height, his shape, his hair, his skin color, etc. The decisions were made and the team came to a conclusion on the overall look of the creature. Over the course of the three films, Gollum's appearance actually changed slightly as the technology advanced and the animators grew more savy with the systems.
Next the team at WETA Digital, the effects team who worked on the trilogy, built a life-size sculpture of Gollum and scanned it into the computer program using lasers. This was an essential step in the process in order to create a computerized 3-D model of the character. Once they had the body created, the team created the character's skeleton, or the articulated framework for the model, in other words. The team also added muscle tone to the framework. This gave the team the ability to allow the computerized character to move with his framework the same way a human body moves in relation to its muscles and bones.
After having an established model to work with, the effects team created a way to control it, much like the way a puppeteer controls a marionette. The team developed "sliders", or a system by which to move individual bones and muscles. In regards to Gollum's face, where detail in the movement is most needed, even the creatures wrinkes and his wisps of hair had their own sliders. Using such sophisticated technology enabled the animators to bring the character to life. They were able to control how he walks, runs, interacts with other characters or objects, etc. For the more detailed and advanced movements, the team placed a series of sensors all over the body of Andy Serkis, the actor who voiced the character and provided the body movements. Using the sensors, they uploaded the movements into their model to bring the character a human-like quality and fluidity to his movements. The final touch was adding clothing and skin tone to the character, complete with pores,blemishes, little hairs, scars, wounds, etc. The genius of the creation is all in the details.
This kind of technology is continuously advancing and it is extremely expensive. The Lord of the Rings was an expensive movie to produce, and the post roduction aspects proved time consuming. Through the tedious efforts of many talented artists and animators, the CGI effects in this film proved to be mind blowing. All in all, the film makers and effects artists involved in this film successfully crafted an unforgettable work of art and managed to tell a compelling story simultaneously.

Web site used can be found at:  http://express.howstuffworks.com/gollum2.htm