On a lighter than usual note:
Layering real physics into classic songs…priceless. This guy (these guys?) talk about string theory and the cosmic microwave background in layered acapella song. Try it and you’ll like it.
Bohemian Gravity: This is the first one I ran into (while looking for talks on quaternions) and gives string theory a bohemian twist.
The Surface of Light: Brings Disney to the cosmic mocrowave background.
Entropic Time: Uses some cool effects to make the point that the arrow of time doesn’t have to be what we think it is.
Defining Gravity: Just saw this one last night and it is wicked cool…
There are more up there…these are just the ones I liked best. Enjoy!