^I agree with Jake about X2 as far as coasters are concerned.
Apart from the Stratosphere Tower rides I'd have to sat it's Götterflug at Belantis, but it can also be the most leisurely ride if you want it to be. If you go for it & try to get the most rotations possible, like loefet, his brother & I have done, then it's immense!
Another great one is Vertigo at Tivoli Gardens, probably the most intense ride during last year's Euro Live (other than the SCAD tower).
Then there's all those crazy German fair rides, with Devil Rock & Transformer being the two most extreme.