Create an amazing animation

I need a very short animation (20-30 sec) created to show snippets of our global, virtual adventure using existing animated characters along the lines of this video [login to view URL] using our avatars and some of the great places and sites entrants "visit" on their global adventure e.g Croatia, India, USA, NZ, Japan, Nepal and more. I like the way they drop through "portals" to move from one place to another in the example given. Could you please give me some examples of work of this type that you have done, so that I can select the most appropriate Freelancer.