UPDATE: As far as I can tell from the tutorial, there is not a whole lot in terms of keying effects to work out that green or blue haze you sometimes will get with chrome keying. Not to mention lack of masks.
How cheap? Free, my brother and sisters. Free as in free air and...and...it's just free, alright. Get the low-down here. I haven't tried it out yet, but I might fool around with it in the coming weeks and let you know how snazzy or not it is.