Brian Holmes presents this podcast where he discusses feed inventories. Brian demonstrates a variety of spreadsheet tools to help with feed calculations. The video is about 1 hour long. Links to tools mentioned in the presentation are below. You may want to expand the video to project to the full screen of your computer.
The video should stream in most browser versions greater than and including: Firefox 3.5, Chrome 3, Internet Explorer 9, Safari 3, Opera 10.5, and IOS (iPhone, iPad, etc.) devices.