Anyone who likes to work with graphics will at one time or another find compositing software useful. Luckily, FOSS has several of the best in Blender and Natron.
Get a quick overview of Natron, cross-platform open source digital compositing software in this new YouTube video.
For the past 10 years, Phil has been working at a public library in the Washington D.C.-area, helping youth and adults use the 28 public Linux stations the library offers seven days a week. He also writes for MAKE magazine, Opensource.com and TechSoup Libraries. Suggest videos by contacting Phil on Twitter or at pshapiro@his.com.