Just getting back into using C2 after spending almost a year getting into a new job. Now I have to convince my wife that I have been good enough to get C3! here is a little challenge- use caustics. get something to look like glass, plastic, a logo, just something cool. This was done rather quickly (10 min, with multiple redoes later playing with textures) made a flattened primitive cube, textured applied physics copied many times and changed the colors, let them fall and rendered the last frame. let's see what you can do.
Another with a little more purpose...
Carrara trans lights works fine, both works looks very good rendered.