Questions on Making a "Glittering" UI effect

I know glittering is the wrong word here. But I am trying to create an effect on the UI buttons for my team's game. I need an effect like the one shown in the Halo 4 pause menu, where a flash of light gradually travels across the buttons. Here's an example:



Notice the bright area. It moves along the edges of the UI button. I image this is done somehow by scrolling a texture across the button somehow, at least that's how I would do it. Seems kinda like a cheap trick to me though. For a better example you can see Spider's video that I snapshotted here: (Skip to around one minute to see the buttons)

Just wait until he opens a pause menu and you can see the effect on the buttons.

Any ideas on how this kind of thing is done?

 

Likely you'll need a shader effect on the texture material of the image you are using for the background, that's where I would start.