Here's an art test that I recently completed for Gameloft Montreal, based on a piece of concept art that they provided. The scene had a very small budget of only 3500 triangles, and only diffuse and alpha textures were allowed, the idea being that it would be able to run on an iPhone. To compare, a current day Xbox 360 or PS3 first-person shooter would use anywhere from 8,000-15,000 triangles on just a gun model alone.
All of the reflections in the scene are faked (ie. the ground plane is transparent, and underneath is a mirrored duplicate of all the objects that I wanted to reflect).
And here's a few renders: