Richard Lenski Ph.D., the Hannah Professor of Microbial Ecology at Michigan State University, speaks in this video about his work on bacterial evolution. He led an experiment in which 50,000 generations of the Escherichia coli bacterium have reproduced since 1988, which is the longest experiment of its kind, ever. Bacteria are a great model for this kind of work, and you can hear more about that in the talk.
He discusses some of the great aspects of this project, such as storing older generations, and then many generations later, comparing the two types and seeing how they differ. That is one way the experiment actually demonstrates evolution in action. He also talks about the insights and advantages we can glean from this project, such as how we can understand the evolution of drug resistance.
Around the halfway point, Lenski gets into another aspect of his research - digital evolution. He is interested in evolving, self-replicating computer programs (like viruses) but instead of being malicious, his team is looking at software that can learn to solve problems, and in that learning, undergoes an evolution. Check out the video to learn more; he does a nice job explaining this work.