Last week we chronicled our top titles on Xbox Live Arcade. Now it's time to examine PlayStation Network. Sony's digital space quickly gained a reputation as the console home for independent, experimental titles, but that perception has slowly been challenged by XBLA's commitment to the space. PSN PLAY may help swing the pendulum back eventually, but that's far from certain. Regardless, the accumulated catalog on PSN is undeniably strong, and we've compiled its very best.