Arrow Dynamics Corkscrew

The original Arrow Corkscrew opened in the late 70's at Knott's Berry Farm.  It was the first successful rollercoaster to turn people upside down, combining two corkscrew inversions with a fairly simple layout.

Vekoma Corkscrew

Vekoma's layouts are more interesting, but the ride is rough.  They come in two main varieties - the Corkscrew with Bayerncurve model (pictured), such as Flamingoland's Corkscrew; and the incredibly compact Whirlwind model, such as Bobbejaanland's Wervelwind.