All the "straight track" on the Beast is actually a series of speed ramps, each of which is designed to continually accelerate the train as it goes through the course, giving the ride an incredible sensation of speed and power. Yes, in recent years, PKI has decided to add brakes to some of these speed ramps, and the effect is diminished, but on those occassions when the trims are turned off, the trains feel like they want to rip from the track. It's so awesome.
As for what makes the ride unique... what other roller coaster careens through the middle of nowhere, is entirely hidden from view anywhere in its park (with exception of lift hills, of course) and ends with a tight, tunnelled helix at 65 mph?
The layout is simple, but with the right combination of tunnel placement, scenery, and of course, SPEED, everything about the Beast just seems to work perfectly, IMHO.
Can you tell I really like the Beast?
I really want to ride Boulder Dash, because that seems to be somewhat in the same category as the Beast, but from what I've seen of it, I don't think it's as unique.