So the particular piece of Mad Scientist geekery causing all the chaos in the two-part pilot of 'Eureka' (including half cows, truncated motor homes and legless sheriffs), turned out to be a ... tachyon generator. I think.
Not sure what this does, exactly, apart from causing hiccups in the space/time continuum. These hiccups result in space/time bubbles that pop up out of the blue and displace whatever they encompass -- be it the end of a motor home, or the unfortunate sheriff's legs.
So what's the use of such a device? Apparently if activated it destabilises the entire space/time continuum, which makes for pretty neat SFX:
Actually, I lie. This is not the End of All Things, but the tachyon generator effectively burping and cancelling out all the earlier bubbles. Or something like that.
Back to the practical applications: perhaps the Eureka scientists can come up with a slightly more portable version that can be used to zap rude drivers, dog poop, or pesky neighbours into alternate timelines.
Meanwhile, what was that thingymabob that crashed into the sheriff's office right at the end?
Let me guess: a tachyon toaster ... ?