Clonezilla

The Free and Open Source Software for Disk Imaging and Cloning
Step-by-step docs

Videos about Clonezilla live usage

On YouTube there are a lot of videos about how to use Clonezilla (more than 9,000 videos in Jan/2014). Here are some about using Clonezilla live:

If you have one and you'd like to be linked here, please email to steven _at_ stevenshiau org.