Sourcing material from the mecca of viral video has always been a bit iffy -- who knows which rabid Beyonce fan will bite back when you slice and dice their Single Ladies tribute video. However, YouTube's recent addition of the Creative Commons licensing option just made it a whole lot easier to make mashups without stepping on anyone's stiletto-sporting toes. Users are now given the option to choose between YouTube's standard license or the Creative Commons Attribution (CC BY) license, which, when
