There have been quite a few game popping up over these past few years making ingenious use of silhouette graphics. Three of my favourites are below. The runaway success of Limbo has, no doubt, had much to do with the trend. I love Outland because if its wonderful fusion of TRON-like luminosity against black, and the forthcoming Forma.8 looks pretty cool too.
In all these instances, un-lit foreground allows the art directors to use more sophisticated (often 3D) effects for explosions and incidental action. In Limbo motes of light dance and a Lord-of-the-Flies world of German expressionism, while in Outland rocks imbued with primitive magic glow as the adventurer strides across them.