If you're a speed freak who lives for the ups and downs of a good ride, here are the top stomach churners and G-force generators in Orlando.

Incredible Hulk Coaster (Islands of Adventure). You'll blast from 0 to 40 mph in 2 seconds, spin upside down more than 100 feet from the ground, and execute seven rollovers and two deep drops on this glow-in-the-dark roller coaster. Can you say, "Pass the Dramamine, puhleeze?"

Rock 'n Roller Coaster (Disney-MGM Studios). You'll launch from 0 to 60 mph in 2.8 seconds and go right into the first inversion as 120 speakers in your "stretch limo" mainline Aerosmith at (yeeeow!) 32,000 watts right into your ears.

Dueling Dragons (Islands of Adventure). Your legs dangle as you do five inversions at 55 to 60 mph and -- get this! -- three times come within 12 inches of the other roller coaster.

Summit Plummet (Disney's Blizzard Beach). This one starts slow, with a lift ride (even in Florida's 100° dog days) to the 120-foot summit. But it finishes with the world's fastest body slide, a test of your courage and swimsuit as it virtually goes straight down and has you moving sans vehicle at 60 mph by the end.

Twilight Zone Tower of Terror (Disney-MGM Studios). The free-fall experiences (there are several scenarios) are more than thrilling -- they're scary. Once your legs stop shaking, some of you will want to ride again.

The Amazing Adventures of Spider-Man (Islands of Adventure). 3-D doesn't get any better than this chase-the-bad-guys ride where you twist, spin, and soar before a simulated 400-foot drop that feels an awful lot like the real thing. It's sure to get your Spidey senses tingling.

Kraken (SeaWorld). This floorless, open-sided coaster uses speed (up to 65 mph), steep climbs, deep drops, and seven loops to create a stomach-churning ride that lasts far too long for some folks.