Gary Klein made most of the early high-end oversized aluminum bikes.  There was a high profile fight with Cannondale over the origins of the oversized aluminum bikes but Klein was generally regarded as the premium bike and Cannondale the production bike.  Neat features are the round into square chain stays, internal cable routing, boxed bottom bracket area (right where the paint fades from orange to pink) and the famous Klein paint (yellow/orange/pink on this one).