Thea for SketchUp is a combination of powerful rendering engines of Thea with the simplicity of SketchUp. Having biased, unbiased and interactive render modes (including GPU support) at your fingertips, inside SketchUp, is an joyful experience. The plugin lets you enrich your models with highly detailed three dimensional content, breaking old limitations related to handled model complexity.
Thea Render comes not only integrated but also with its own standalone application (Studio) with various tools, material editor and advanced staging operations.
Find more info here: http://www.thearender.com/sketchup