Ooooh yeah. (We aren't talking electricity here, of course, as the monitor has its own power supply.)
If you can view that link I gave above, to the AU Apple site ... though it might jump to US for you ... you see it's just a basic MacBook Air connected to the big screen, so if that can do it, a MacBook Pro sure can.
It's pretty awesome. You can either view the same thing on both screens, or have something different showing on both—like your Photoshop palettes on the laptop and just the Ps document on the big screen ... lots of possibilities. You can even daisy chain those big monitors in a long line. Pretty awesome, but also pretty $$$.