"Rains of Castamere"

Game of Thrones is getting increasingly clever in its use of the rather mournful "Rains of Castamere" as a leitmotif for the mounting tragedy of the Lannister clan. Best use to date, I think, was the most recent episode, where the "And so he spoke, and so he spoke" part, played on cellos, emerges out of the mostly unrelated background music immediately after Tyrion's (amazing, potentially Emmy-worthy) speech at the end of his trial, leading into a full, cello-heavy instrumental version playing behind the ending credits. Ramin Djawadi, the composer for the series, doesn't get anywhere near enough credit, in my opinion.