And even this lame cloned dreams doesn't apply to 3 monitors (2 video cards), etc. 
Some dreams, the programmed ones, SCREAM for dual/tri monitor support. Who wants to see the same Photo Collage, for example, on both monitors, rather than one lrge photo collage across all of them.
The easiest way to accomplish this would be to allow two instances of DreamScene to play at the same time, and then select which monitor each instance is displaying on (the way ObjectDock already does with docks, for example).
Yes it would double the CPU resources, but Vista was designed to handle this. Unlike XP (which doesn't thread its codecs and has a broken hardware acceleration across multiple monitors issue), Vista will let you play multiple videos on multiple monitors at full speed without conflict if you have the horsepower to handle it.
I work with 5 monitors across three computers all Multiplicity'd together for 20 hours every day, so yeah, I'd PAY $$ for DreamScene Pro if it had this feature. 8)